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Posted to commits@hawq.apache.org by rv...@apache.org on 2015/09/22 21:14:12 UTC

[09/35] incubator-hawq git commit: SGA import. Now with files previously missing because of the .gitignore issue

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/emitter.py
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diff --git a/tools/bin/ext/yaml/emitter.py b/tools/bin/ext/yaml/emitter.py
new file mode 100644
index 0000000..d9d1bf8
--- /dev/null
+++ b/tools/bin/ext/yaml/emitter.py
@@ -0,0 +1,1163 @@
+
+# Emitter expects events obeying the following grammar:
+# stream ::= STREAM-START document* STREAM-END
+# document ::= DOCUMENT-START node DOCUMENT-END
+# node ::= SCALAR | sequence | mapping
+# sequence ::= SEQUENCE-START node* SEQUENCE-END
+# mapping ::= MAPPING-START (node node)* MAPPING-END
+
+__all__ = ['Emitter', 'EmitterError']
+
+from error import YAMLError
+from events import *
+
+import re
+
+class EmitterError(YAMLError):
+    pass
+
+class ScalarAnalysis(object):
+    def __init__(self, scalar, empty, multiline,
+            allow_flow_plain, allow_block_plain,
+            allow_single_quoted, allow_double_quoted,
+            allow_block):
+        self.scalar = scalar
+        self.empty = empty
+        self.multiline = multiline
+        self.allow_flow_plain = allow_flow_plain
+        self.allow_block_plain = allow_block_plain
+        self.allow_single_quoted = allow_single_quoted
+        self.allow_double_quoted = allow_double_quoted
+        self.allow_block = allow_block
+
+class Emitter(object):
+
+    DEFAULT_TAG_PREFIXES = {
+        u'!' : u'!',
+        u'tag:yaml.org,2002:' : u'!!',
+    }
+
+    def __init__(self, stream, canonical=None, indent=None, width=None,
+            allow_unicode=None, line_break=None):
+
+        # The stream should have the methods `write` and possibly `flush`.
+        self.stream = stream
+
+        # Encoding can be overriden by STREAM-START.
+        self.encoding = None
+
+        # Emitter is a state machine with a stack of states to handle nested
+        # structures.
+        self.states = []
+        self.state = self.expect_stream_start
+
+        # Current event and the event queue.
+        self.events = []
+        self.event = None
+
+        # The current indentation level and the stack of previous indents.
+        self.indents = []
+        self.indent = None
+
+        # Flow level.
+        self.flow_level = 0
+
+        # Contexts.
+        self.root_context = False
+        self.sequence_context = False
+        self.mapping_context = False
+        self.simple_key_context = False
+
+        # Characteristics of the last emitted character:
+        #  - current position.
+        #  - is it a whitespace?
+        #  - is it an indention character
+        #    (indentation space, '-', '?', or ':')?
+        self.line = 0
+        self.column = 0
+        self.whitespace = True
+        self.indention = True
+
+        # Formatting details.
+        self.canonical = canonical
+        self.allow_unicode = allow_unicode
+        self.best_indent = 2
+        if indent and 1 < indent < 10:
+            self.best_indent = indent
+        self.best_width = 80
+        if width and width > self.best_indent*2:
+            self.best_width = width
+        self.best_line_break = u'\n'
+        if line_break in [u'\r', u'\n', u'\r\n']:
+            self.best_line_break = line_break
+
+        # Tag prefixes.
+        self.tag_prefixes = None
+
+        # Prepared anchor and tag.
+        self.prepared_anchor = None
+        self.prepared_tag = None
+
+        # Scalar analysis and style.
+        self.analysis = None
+        self.style = None
+
+    def emit(self, event):
+        self.events.append(event)
+        while not self.need_more_events():
+            self.event = self.events.pop(0)
+            self.state()
+            self.event = None
+
+    # In some cases, we wait for a few next events before emitting.
+
+    def need_more_events(self):
+        if not self.events:
+            return True
+        event = self.events[0]
+        if isinstance(event, DocumentStartEvent):
+            return self.need_events(1)
+        elif isinstance(event, SequenceStartEvent):
+            return self.need_events(2)
+        elif isinstance(event, MappingStartEvent):
+            return self.need_events(3)
+        else:
+            return False
+
+    def need_events(self, count):
+        level = 0
+        for event in self.events[1:]:
+            if isinstance(event, (DocumentStartEvent, CollectionStartEvent)):
+                level += 1
+            elif isinstance(event, (DocumentEndEvent, CollectionEndEvent)):
+                level -= 1
+            elif isinstance(event, StreamEndEvent):
+                level = -1
+            if level < 0:
+                return False
+        return (len(self.events) < count+1)
+
+    def increase_indent(self, flow=False, indentless=False):
+        self.indents.append(self.indent)
+        if self.indent is None:
+            if flow:
+                self.indent = self.best_indent
+            else:
+                self.indent = 0
+        elif not indentless:
+            self.indent += self.best_indent
+
+    # States.
+
+    # Stream handlers.
+
+    def expect_stream_start(self):
+        if isinstance(self.event, StreamStartEvent):
+            if self.event.encoding:
+                self.encoding = self.event.encoding
+            self.write_stream_start()
+            self.state = self.expect_first_document_start
+        else:
+            raise EmitterError("expected StreamStartEvent, but got %s"
+                    % self.event)
+
+    def expect_nothing(self):
+        raise EmitterError("expected nothing, but got %s" % self.event)
+
+    # Document handlers.
+
+    def expect_first_document_start(self):
+        return self.expect_document_start(first=True)
+
+    def expect_document_start(self, first=False):
+        if isinstance(self.event, DocumentStartEvent):
+            if self.event.version:
+                version_text = self.prepare_version(self.event.version)
+                self.write_version_directive(version_text)
+            self.tag_prefixes = self.DEFAULT_TAG_PREFIXES.copy()
+            if self.event.tags:
+                handles = self.event.tags.keys()
+                handles.sort()
+                for handle in handles:
+                    prefix = self.event.tags[handle]
+                    self.tag_prefixes[prefix] = handle
+                    handle_text = self.prepare_tag_handle(handle)
+                    prefix_text = self.prepare_tag_prefix(prefix)
+                    self.write_tag_directive(handle_text, prefix_text)
+            implicit = (first and not self.event.explicit and not self.canonical
+                    and not self.event.version and not self.event.tags
+                    and not self.check_empty_document())
+            if not implicit:
+                self.write_indent()
+                self.write_indicator(u'---', True)
+                if self.canonical:
+                    self.write_indent()
+            self.state = self.expect_document_root
+        elif isinstance(self.event, StreamEndEvent):
+            self.write_stream_end()
+            self.state = self.expect_nothing
+        else:
+            raise EmitterError("expected DocumentStartEvent, but got %s"
+                    % self.event)
+
+    def expect_document_end(self):
+        if isinstance(self.event, DocumentEndEvent):
+            self.write_indent()
+            if self.event.explicit:
+                self.write_indicator(u'...', True)
+                self.write_indent()
+            self.flush_stream()
+            self.state = self.expect_document_start
+        else:
+            raise EmitterError("expected DocumentEndEvent, but got %s"
+                    % self.event)
+
+    def expect_document_root(self):
+        self.states.append(self.expect_document_end)
+        self.expect_node(root=True)
+
+    # Node handlers.
+
+    def expect_node(self, root=False, sequence=False, mapping=False,
+            simple_key=False):
+        self.root_context = root
+        self.sequence_context = sequence
+        self.mapping_context = mapping
+        self.simple_key_context = simple_key
+        if isinstance(self.event, AliasEvent):
+            self.expect_alias()
+        elif isinstance(self.event, (ScalarEvent, CollectionStartEvent)):
+            self.process_anchor(u'&')
+            self.process_tag()
+            if isinstance(self.event, ScalarEvent):
+                self.expect_scalar()
+            elif isinstance(self.event, SequenceStartEvent):
+                if self.flow_level or self.canonical or self.event.flow_style   \
+                        or self.check_empty_sequence():
+                    self.expect_flow_sequence()
+                else:
+                    self.expect_block_sequence()
+            elif isinstance(self.event, MappingStartEvent):
+                if self.flow_level or self.canonical or self.event.flow_style   \
+                        or self.check_empty_mapping():
+                    self.expect_flow_mapping()
+                else:
+                    self.expect_block_mapping()
+        else:
+            raise EmitterError("expected NodeEvent, but got %s" % self.event)
+
+    def expect_alias(self):
+        if self.event.anchor is None:
+            raise EmitterError("anchor is not specified for alias")
+        self.process_anchor(u'*')
+        self.state = self.states.pop()
+
+    def expect_scalar(self):
+        self.increase_indent(flow=True)
+        self.process_scalar()
+        self.indent = self.indents.pop()
+        self.state = self.states.pop()
+
+    # Flow sequence handlers.
+
+    def expect_flow_sequence(self):
+        self.write_indicator(u'[', True, whitespace=True)
+        self.flow_level += 1
+        self.increase_indent(flow=True)
+        self.state = self.expect_first_flow_sequence_item
+
+    def expect_first_flow_sequence_item(self):
+        if isinstance(self.event, SequenceEndEvent):
+            self.indent = self.indents.pop()
+            self.flow_level -= 1
+            self.write_indicator(u']', False)
+            self.state = self.states.pop()
+        else:
+            if self.canonical or self.column > self.best_width:
+                self.write_indent()
+            self.states.append(self.expect_flow_sequence_item)
+            self.expect_node(sequence=True)
+
+    def expect_flow_sequence_item(self):
+        if isinstance(self.event, SequenceEndEvent):
+            self.indent = self.indents.pop()
+            self.flow_level -= 1
+            if self.canonical:
+                self.write_indicator(u',', False)
+                self.write_indent()
+            self.write_indicator(u']', False)
+            self.state = self.states.pop()
+        else:
+            self.write_indicator(u',', False)
+            if self.canonical or self.column > self.best_width:
+                self.write_indent()
+            self.states.append(self.expect_flow_sequence_item)
+            self.expect_node(sequence=True)
+
+    # Flow mapping handlers.
+
+    def expect_flow_mapping(self):
+        self.write_indicator(u'{', True, whitespace=True)
+        self.flow_level += 1
+        self.increase_indent(flow=True)
+        self.state = self.expect_first_flow_mapping_key
+
+    def expect_first_flow_mapping_key(self):
+        if isinstance(self.event, MappingEndEvent):
+            self.indent = self.indents.pop()
+            self.flow_level -= 1
+            self.write_indicator(u'}', False)
+            self.state = self.states.pop()
+        else:
+            if self.canonical or self.column > self.best_width:
+                self.write_indent()
+            if not self.canonical and self.check_simple_key():
+                self.states.append(self.expect_flow_mapping_simple_value)
+                self.expect_node(mapping=True, simple_key=True)
+            else:
+                self.write_indicator(u'?', True)
+                self.states.append(self.expect_flow_mapping_value)
+                self.expect_node(mapping=True)
+
+    def expect_flow_mapping_key(self):
+        if isinstance(self.event, MappingEndEvent):
+            self.indent = self.indents.pop()
+            self.flow_level -= 1
+            if self.canonical:
+                self.write_indicator(u',', False)
+                self.write_indent()
+            self.write_indicator(u'}', False)
+            self.state = self.states.pop()
+        else:
+            self.write_indicator(u',', False)
+            if self.canonical or self.column > self.best_width:
+                self.write_indent()
+            if not self.canonical and self.check_simple_key():
+                self.states.append(self.expect_flow_mapping_simple_value)
+                self.expect_node(mapping=True, simple_key=True)
+            else:
+                self.write_indicator(u'?', True)
+                self.states.append(self.expect_flow_mapping_value)
+                self.expect_node(mapping=True)
+
+    def expect_flow_mapping_simple_value(self):
+        self.write_indicator(u':', False)
+        self.states.append(self.expect_flow_mapping_key)
+        self.expect_node(mapping=True)
+
+    def expect_flow_mapping_value(self):
+        if self.canonical or self.column > self.best_width:
+            self.write_indent()
+        self.write_indicator(u':', True)
+        self.states.append(self.expect_flow_mapping_key)
+        self.expect_node(mapping=True)
+
+    # Block sequence handlers.
+
+    def expect_block_sequence(self):
+        indentless = (self.mapping_context and not self.indention)
+        self.increase_indent(flow=False, indentless=indentless)
+        self.state = self.expect_first_block_sequence_item
+
+    def expect_first_block_sequence_item(self):
+        return self.expect_block_sequence_item(first=True)
+
+    def expect_block_sequence_item(self, first=False):
+        if not first and isinstance(self.event, SequenceEndEvent):
+            self.indent = self.indents.pop()
+            self.state = self.states.pop()
+        else:
+            self.write_indent()
+            self.write_indicator(u'-', True, indention=True)
+            self.states.append(self.expect_block_sequence_item)
+            self.expect_node(sequence=True)
+
+    # Block mapping handlers.
+
+    def expect_block_mapping(self):
+        self.increase_indent(flow=False)
+        self.state = self.expect_first_block_mapping_key
+
+    def expect_first_block_mapping_key(self):
+        return self.expect_block_mapping_key(first=True)
+
+    def expect_block_mapping_key(self, first=False):
+        if not first and isinstance(self.event, MappingEndEvent):
+            self.indent = self.indents.pop()
+            self.state = self.states.pop()
+        else:
+            self.write_indent()
+            if self.check_simple_key():
+                self.states.append(self.expect_block_mapping_simple_value)
+                self.expect_node(mapping=True, simple_key=True)
+            else:
+                self.write_indicator(u'?', True, indention=True)
+                self.states.append(self.expect_block_mapping_value)
+                self.expect_node(mapping=True)
+
+    def expect_block_mapping_simple_value(self):
+        self.write_indicator(u':', False)
+        self.states.append(self.expect_block_mapping_key)
+        self.expect_node(mapping=True)
+
+    def expect_block_mapping_value(self):
+        self.write_indent()
+        self.write_indicator(u':', True, indention=True)
+        self.states.append(self.expect_block_mapping_key)
+        self.expect_node(mapping=True)
+
+    # Checkers.
+
+    def check_empty_sequence(self):
+        return (isinstance(self.event, SequenceStartEvent) and self.events
+                and isinstance(self.events[0], SequenceEndEvent))
+
+    def check_empty_mapping(self):
+        return (isinstance(self.event, MappingStartEvent) and self.events
+                and isinstance(self.events[0], MappingEndEvent))
+
+    def check_empty_document(self):
+        if not isinstance(self.event, DocumentStartEvent) or not self.events:
+            return False
+        event = self.events[0]
+        return (isinstance(event, ScalarEvent) and event.anchor is None
+                and event.tag is None and event.implicit and event.value == u'')
+
+    def check_simple_key(self):
+        length = 0
+        if isinstance(self.event, NodeEvent) and self.event.anchor is not None:
+            if self.prepared_anchor is None:
+                self.prepared_anchor = self.prepare_anchor(self.event.anchor)
+            length += len(self.prepared_anchor)
+        if isinstance(self.event, (ScalarEvent, CollectionStartEvent))  \
+                and self.event.tag is not None:
+            if self.prepared_tag is None:
+                self.prepared_tag = self.prepare_tag(self.event.tag)
+            length += len(self.prepared_tag)
+        if isinstance(self.event, ScalarEvent):
+            if self.analysis is None:
+                self.analysis = self.analyze_scalar(self.event.value)
+            length += len(self.analysis.scalar)
+        return (length < 128 and (isinstance(self.event, AliasEvent)
+            or (isinstance(self.event, ScalarEvent)
+                    and not self.analysis.empty and not self.analysis.multiline)
+            or self.check_empty_sequence() or self.check_empty_mapping()))
+
+    # Anchor, Tag, and Scalar processors.
+
+    def process_anchor(self, indicator):
+        if self.event.anchor is None:
+            self.prepared_anchor = None
+            return
+        if self.prepared_anchor is None:
+            self.prepared_anchor = self.prepare_anchor(self.event.anchor)
+        if self.prepared_anchor:
+            self.write_indicator(indicator+self.prepared_anchor, True)
+        self.prepared_anchor = None
+
+    def process_tag(self):
+        tag = self.event.tag
+        if isinstance(self.event, ScalarEvent):
+            if self.style is None:
+                self.style = self.choose_scalar_style()
+            if ((not self.canonical or tag is None) and
+                ((self.style == '' and self.event.implicit[0])
+                        or (self.style != '' and self.event.implicit[1]))):
+                self.prepared_tag = None
+                return
+            if self.event.implicit[0] and tag is None:
+                tag = u'!'
+                self.prepared_tag = None
+        else:
+            if (not self.canonical or tag is None) and self.event.implicit:
+                self.prepared_tag = None
+                return
+        if tag is None:
+            raise EmitterError("tag is not specified")
+        if self.prepared_tag is None:
+            self.prepared_tag = self.prepare_tag(tag)
+        if self.prepared_tag:
+            self.write_indicator(self.prepared_tag, True)
+        self.prepared_tag = None
+
+    def choose_scalar_style(self):
+        if self.analysis is None:
+            self.analysis = self.analyze_scalar(self.event.value)
+        if self.event.style == '"' or self.canonical:
+            return '"'
+        if not self.event.style and self.event.implicit[0]:
+            if (not (self.simple_key_context and
+                    (self.analysis.empty or self.analysis.multiline))
+                and (self.flow_level and self.analysis.allow_flow_plain
+                    or (not self.flow_level and self.analysis.allow_block_plain))):
+                return ''
+        if self.event.style and self.event.style in '|>':
+            if (not self.flow_level and not self.simple_key_context
+                    and self.analysis.allow_block):
+                return self.event.style
+        if not self.event.style or self.event.style == '\'':
+            if (self.analysis.allow_single_quoted and
+                    not (self.simple_key_context and self.analysis.multiline)):
+                return '\''
+        return '"'
+
+    def process_scalar(self):
+        if self.analysis is None:
+            self.analysis = self.analyze_scalar(self.event.value)
+        if self.style is None:
+            self.style = self.choose_scalar_style()
+        split = (not self.simple_key_context)
+        #if self.analysis.multiline and split    \
+        #        and (not self.style or self.style in '\'\"'):
+        #    self.write_indent()
+        if self.style == '"':
+            self.write_double_quoted(self.analysis.scalar, split)
+        elif self.style == '\'':
+            self.write_single_quoted(self.analysis.scalar, split)
+        elif self.style == '>':
+            self.write_folded(self.analysis.scalar)
+        elif self.style == '|':
+            self.write_literal(self.analysis.scalar)
+        else:
+            self.write_plain(self.analysis.scalar, split)
+        self.analysis = None
+        self.style = None
+
+    # Analyzers.
+
+    def prepare_version(self, version):
+        major, minor = version
+        if major != 1:
+            raise EmitterError("unsupported YAML version: %d.%d" % (major, minor))
+        return u'%d.%d' % (major, minor)
+
+    def prepare_tag_handle(self, handle):
+        if not handle:
+            raise EmitterError("tag handle must not be empty")
+        if handle[0] != u'!' or handle[-1] != u'!':
+            raise EmitterError("tag handle must start and end with '!': %r"
+                    % (handle.encode('utf-8')))
+        for ch in handle[1:-1]:
+            if not (u'0' <= ch <= u'9' or u'A' <= ch <= 'Z' or u'a' <= ch <= 'z'    \
+                    or ch in u'-_'):
+                raise EmitterError("invalid character %r in the tag handle: %r"
+                        % (ch.encode('utf-8'), handle.encode('utf-8')))
+        return handle
+
+    def prepare_tag_prefix(self, prefix):
+        if not prefix:
+            raise EmitterError("tag prefix must not be empty")
+        chunks = []
+        start = end = 0
+        if prefix[0] == u'!':
+            end = 1
+        while end < len(prefix):
+            ch = prefix[end]
+            if u'0' <= ch <= u'9' or u'A' <= ch <= 'Z' or u'a' <= ch <= 'z'  \
+                    or ch in u'-;/?!:@&=+$,_.~*\'()[]':
+                end += 1
+            else:
+                if start < end:
+                    chunks.append(prefix[start:end])
+                start = end = end+1
+                data = ch.encode('utf-8')
+                for ch in data:
+                    chunks.append(u'%%%02X' % ord(ch))
+        if start < end:
+            chunks.append(prefix[start:end])
+        return u''.join(chunks)
+
+    def prepare_tag(self, tag):
+        if not tag:
+            raise EmitterError("tag must not be empty")
+        if tag == u'!':
+            return tag
+        handle = None
+        suffix = tag
+        for prefix in self.tag_prefixes:
+            if tag.startswith(prefix)   \
+                    and (prefix == u'!' or len(prefix) < len(tag)):
+                handle = self.tag_prefixes[prefix]
+                suffix = tag[len(prefix):]
+        chunks = []
+        start = end = 0
+        while end < len(suffix):
+            ch = suffix[end]
+            if u'0' <= ch <= u'9' or u'A' <= ch <= 'Z' or u'a' <= ch <= 'z'  \
+                    or ch in u'-;/?:@&=+$,_.~*\'()[]'   \
+                    or (ch == u'!' and handle != u'!'):
+                end += 1
+            else:
+                if start < end:
+                    chunks.append(suffix[start:end])
+                start = end = end+1
+                data = ch.encode('utf-8')
+                for ch in data:
+                    chunks.append(u'%%%02X' % ord(ch))
+        if start < end:
+            chunks.append(suffix[start:end])
+        suffix_text = u''.join(chunks)
+        if handle:
+            return u'%s%s' % (handle, suffix_text)
+        else:
+            return u'!<%s>' % suffix_text
+
+    def prepare_anchor(self, anchor):
+        if not anchor:
+            raise EmitterError("anchor must not be empty")
+        for ch in anchor:
+            if not (u'0' <= ch <= u'9' or u'A' <= ch <= 'Z' or u'a' <= ch <= 'z'    \
+                    or ch in u'-_'):
+                raise EmitterError("invalid character %r in the anchor: %r"
+                        % (ch.encode('utf-8'), anchor.encode('utf-8')))
+        return anchor
+
+    def analyze_scalar(self, scalar):
+
+        # Empty scalar is a special case.
+        if not scalar:
+            return ScalarAnalysis(scalar=scalar, empty=True, multiline=False,
+                    allow_flow_plain=False, allow_block_plain=True,
+                    allow_single_quoted=True, allow_double_quoted=True,
+                    allow_block=False)
+
+        # Indicators and special characters.
+        block_indicators = False
+        flow_indicators = False
+        line_breaks = False
+        special_characters = False
+
+        # Whitespaces.
+        inline_spaces = False          # non-space space+ non-space
+        inline_breaks = False          # non-space break+ non-space
+        leading_spaces = False         # ^ space+ (non-space | $)
+        leading_breaks = False         # ^ break+ (non-space | $)
+        trailing_spaces = False        # (^ | non-space) space+ $
+        trailing_breaks = False        # (^ | non-space) break+ $
+        inline_breaks_spaces = False   # non-space break+ space+ non-space
+        mixed_breaks_spaces = False    # anything else
+
+        # Check document indicators.
+        if scalar.startswith(u'---') or scalar.startswith(u'...'):
+            block_indicators = True
+            flow_indicators = True
+
+        # First character or preceded by a whitespace.
+        preceeded_by_space = True
+
+        # Last character or followed by a whitespace.
+        followed_by_space = (len(scalar) == 1 or
+                scalar[1] in u'\0 \t\r\n\x85\u2028\u2029')
+
+        # The current series of whitespaces contain plain spaces.
+        spaces = False
+
+        # The current series of whitespaces contain line breaks.
+        breaks = False
+
+        # The current series of whitespaces contain a space followed by a
+        # break.
+        mixed = False
+
+        # The current series of whitespaces start at the beginning of the
+        # scalar.
+        leading = False
+
+        index = 0
+        while index < len(scalar):
+            ch = scalar[index]
+
+            # Check for indicators.
+
+            if index == 0:
+                # Leading indicators are special characters.
+                if ch in u'#,[]{}&*!|>\'\"%@`': 
+                    flow_indicators = True
+                    block_indicators = True
+                if ch in u'?:':
+                    flow_indicators = True
+                    if followed_by_space:
+                        block_indicators = True
+                if ch == u'-' and followed_by_space:
+                    flow_indicators = True
+                    block_indicators = True
+            else:
+                # Some indicators cannot appear within a scalar as well.
+                if ch in u',?[]{}':
+                    flow_indicators = True
+                if ch == u':':
+                    flow_indicators = True
+                    if followed_by_space:
+                        block_indicators = True
+                if ch == u'#' and preceeded_by_space:
+                    flow_indicators = True
+                    block_indicators = True
+
+            # Check for line breaks, special, and unicode characters.
+
+            if ch in u'\n\x85\u2028\u2029':
+                line_breaks = True
+            if not (ch == u'\n' or u'\x20' <= ch <= u'\x7E'):
+                if (ch == u'\x85' or u'\xA0' <= ch <= u'\uD7FF'
+                        or u'\uE000' <= ch <= u'\uFFFD') and ch != u'\uFEFF':
+                    unicode_characters = True
+                    if not self.allow_unicode:
+                        special_characters = True
+                else:
+                    special_characters = True
+
+            # Spaces, line breaks, and how they are mixed. State machine.
+
+            # Start or continue series of whitespaces.
+            if ch in u' \n\x85\u2028\u2029':
+                if spaces and breaks:
+                    if ch != u' ':      # break+ (space+ break+)    => mixed
+                        mixed = True
+                elif spaces:
+                    if ch != u' ':      # (space+ break+)   => mixed
+                        breaks = True
+                        mixed = True
+                elif breaks:
+                    if ch == u' ':      # break+ space+
+                        spaces = True
+                else:
+                    leading = (index == 0)
+                    if ch == u' ':      # space+
+                        spaces = True
+                    else:               # break+
+                        breaks = True
+
+            # Series of whitespaces ended with a non-space.
+            elif spaces or breaks:
+                if leading:
+                    if spaces and breaks:
+                        mixed_breaks_spaces = True
+                    elif spaces:
+                        leading_spaces = True
+                    elif breaks:
+                        leading_breaks = True
+                else:
+                    if mixed:
+                        mixed_breaks_spaces = True
+                    elif spaces and breaks:
+                        inline_breaks_spaces = True
+                    elif spaces:
+                        inline_spaces = True
+                    elif breaks:
+                        inline_breaks = True
+                spaces = breaks = mixed = leading = False
+
+            # Series of whitespaces reach the end.
+            if (spaces or breaks) and (index == len(scalar)-1):
+                if spaces and breaks:
+                    mixed_breaks_spaces = True
+                elif spaces:
+                    trailing_spaces = True
+                    if leading:
+                        leading_spaces = True
+                elif breaks:
+                    trailing_breaks = True
+                    if leading:
+                        leading_breaks = True
+                spaces = breaks = mixed = leading = False
+
+            # Prepare for the next character.
+            index += 1
+            preceeded_by_space = (ch in u'\0 \t\r\n\x85\u2028\u2029')
+            followed_by_space = (index+1 >= len(scalar) or
+                    scalar[index+1] in u'\0 \t\r\n\x85\u2028\u2029')
+
+        # Let's decide what styles are allowed.
+        allow_flow_plain = True
+        allow_block_plain = True
+        allow_single_quoted = True
+        allow_double_quoted = True
+        allow_block = True
+
+        # Leading and trailing whitespace are bad for plain scalars. We also
+        # do not want to mess with leading whitespaces for block scalars.
+        if leading_spaces or leading_breaks or trailing_spaces:
+            allow_flow_plain = allow_block_plain = allow_block = False
+
+        # Trailing breaks are fine for block scalars, but unacceptable for
+        # plain scalars.
+        if trailing_breaks:
+            allow_flow_plain = allow_block_plain = False
+
+        # The combination of (space+ break+) is only acceptable for block
+        # scalars.
+        if inline_breaks_spaces:
+            allow_flow_plain = allow_block_plain = allow_single_quoted = False
+
+        # Mixed spaces and breaks, as well as special character are only
+        # allowed for double quoted scalars.
+        if mixed_breaks_spaces or special_characters:
+            allow_flow_plain = allow_block_plain =  \
+            allow_single_quoted = allow_block = False
+
+        # We don't emit multiline plain scalars.
+        if line_breaks:
+            allow_flow_plain = allow_block_plain = False
+
+        # Flow indicators are forbidden for flow plain scalars.
+        if flow_indicators:
+            allow_flow_plain = False
+
+        # Block indicators are forbidden for block plain scalars.
+        if block_indicators:
+            allow_block_plain = False
+
+        return ScalarAnalysis(scalar=scalar,
+                empty=False, multiline=line_breaks,
+                allow_flow_plain=allow_flow_plain,
+                allow_block_plain=allow_block_plain,
+                allow_single_quoted=allow_single_quoted,
+                allow_double_quoted=allow_double_quoted,
+                allow_block=allow_block)
+
+    # Writers.
+
+    def flush_stream(self):
+        if hasattr(self.stream, 'flush'):
+            self.stream.flush()
+
+    def write_stream_start(self):
+        # Write BOM if needed.
+        if self.encoding and self.encoding.startswith('utf-16'):
+            self.stream.write(u'\xFF\xFE'.encode(self.encoding))
+
+    def write_stream_end(self):
+        self.flush_stream()
+
+    def write_indicator(self, indicator, need_whitespace,
+            whitespace=False, indention=False):
+        if self.whitespace or not need_whitespace:
+            data = indicator
+        else:
+            data = u' '+indicator
+        self.whitespace = whitespace
+        self.indention = self.indention and indention
+        self.column += len(data)
+        if self.encoding:
+            data = data.encode(self.encoding)
+        self.stream.write(data)
+
+    def write_indent(self):
+        indent = self.indent or 0
+        if not self.indention or self.column > indent   \
+                or (self.column == indent and not self.whitespace):
+            self.write_line_break()
+        if self.column < indent:
+            self.whitespace = True
+            data = u' '*(indent-self.column)
+            self.column = indent
+            if self.encoding:
+                data = data.encode(self.encoding)
+            self.stream.write(data)
+
+    def write_line_break(self, data=None):
+        if data is None:
+            data = self.best_line_break
+        self.whitespace = True
+        self.indention = True
+        self.line += 1
+        self.column = 0
+        if self.encoding:
+            data = data.encode(self.encoding)
+        self.stream.write(data)
+
+    def write_version_directive(self, version_text):
+        data = u'%%YAML %s' % version_text
+        if self.encoding:
+            data = data.encode(self.encoding)
+        self.stream.write(data)
+        self.write_line_break()
+
+    def write_tag_directive(self, handle_text, prefix_text):
+        data = u'%%TAG %s %s' % (handle_text, prefix_text)
+        if self.encoding:
+            data = data.encode(self.encoding)
+        self.stream.write(data)
+        self.write_line_break()
+
+    # Scalar streams.
+
+    def write_single_quoted(self, text, split=True):
+        self.write_indicator(u'\'', True)
+        spaces = False
+        breaks = False
+        start = end = 0
+        while end <= len(text):
+            ch = None
+            if end < len(text):
+                ch = text[end]
+            if spaces:
+                if ch is None or ch != u' ':
+                    if start+1 == end and self.column > self.best_width and split   \
+                            and start != 0 and end != len(text):
+                        self.write_indent()
+                    else:
+                        data = text[start:end]
+                        self.column += len(data)
+                        if self.encoding:
+                            data = data.encode(self.encoding)
+                        self.stream.write(data)
+                    start = end
+            elif breaks:
+                if ch is None or ch not in u'\n\x85\u2028\u2029':
+                    if text[start] == u'\n':
+                        self.write_line_break()
+                    for br in text[start:end]:
+                        if br == u'\n':
+                            self.write_line_break()
+                        else:
+                            self.write_line_break(br)
+                    self.write_indent()
+                    start = end
+            else:
+                if ch is None or ch in u' \n\x85\u2028\u2029' or ch == u'\'':
+                    if start < end:
+                        data = text[start:end]
+                        self.column += len(data)
+                        if self.encoding:
+                            data = data.encode(self.encoding)
+                        self.stream.write(data)
+                        start = end
+            if ch == u'\'':
+                data = u'\'\''
+                self.column += 2
+                if self.encoding:
+                    data = data.encode(self.encoding)
+                self.stream.write(data)
+                start = end + 1
+            if ch is not None:
+                spaces = (ch == u' ')
+                breaks = (ch in u'\n\x85\u2028\u2029')
+            end += 1
+        self.write_indicator(u'\'', False)
+
+    ESCAPE_REPLACEMENTS = {
+        u'\0':      u'0',
+        u'\x07':    u'a',
+        u'\x08':    u'b',
+        u'\x09':    u't',
+        u'\x0A':    u'n',
+        u'\x0B':    u'v',
+        u'\x0C':    u'f',
+        u'\x0D':    u'r',
+        u'\x1B':    u'e',
+        u'\"':      u'\"',
+        u'\\':      u'\\',
+        u'\x85':    u'N',
+        u'\xA0':    u'_',
+        u'\u2028':  u'L',
+        u'\u2029':  u'P',
+    }
+
+    def write_double_quoted(self, text, split=True):
+        self.write_indicator(u'"', True)
+        start = end = 0
+        while end <= len(text):
+            ch = None
+            if end < len(text):
+                ch = text[end]
+            if ch is None or ch in u'"\\\x85\u2028\u2029\uFEFF' \
+                    or not (u'\x20' <= ch <= u'\x7E'
+                        or (self.allow_unicode
+                            and (u'\xA0' <= ch <= u'\uD7FF'
+                                or u'\uE000' <= ch <= u'\uFFFD'))):
+                if start < end:
+                    data = text[start:end]
+                    self.column += len(data)
+                    if self.encoding:
+                        data = data.encode(self.encoding)
+                    self.stream.write(data)
+                    start = end
+                if ch is not None:
+                    if ch in self.ESCAPE_REPLACEMENTS:
+                        data = u'\\'+self.ESCAPE_REPLACEMENTS[ch]
+                    elif ch <= u'\xFF':
+                        data = u'\\x%02X' % ord(ch)
+                    elif ch <= u'\uFFFF':
+                        data = u'\\u%04X' % ord(ch)
+                    else:
+                        data = u'\\U%08X' % ord(ch)
+                    self.column += len(data)
+                    if self.encoding:
+                        data = data.encode(self.encoding)
+                    self.stream.write(data)
+                    start = end+1
+            if 0 < end < len(text)-1 and (ch == u' ' or start >= end)   \
+                    and self.column+(end-start) > self.best_width and split:
+                data = text[start:end]+u'\\'
+                if start < end:
+                    start = end
+                self.column += len(data)
+                if self.encoding:
+                    data = data.encode(self.encoding)
+                self.stream.write(data)
+                self.write_indent()
+                self.whitespace = False
+                self.indention = False
+                if text[start] == u' ':
+                    data = u'\\'
+                    self.column += len(data)
+                    if self.encoding:
+                        data = data.encode(self.encoding)
+                    self.stream.write(data)
+            end += 1
+        self.write_indicator(u'"', False)
+
+    def determine_chomp(self, text):
+        tail = text[-2:]
+        while len(tail) < 2:
+            tail = u' '+tail
+        if tail[-1] in u'\n\x85\u2028\u2029':
+            if tail[-2] in u'\n\x85\u2028\u2029':
+                return u'+'
+            else:
+                return u''
+        else:
+            return u'-'
+
+    def write_folded(self, text):
+        chomp = self.determine_chomp(text)
+        self.write_indicator(u'>'+chomp, True)
+        self.write_indent()
+        leading_space = False
+        spaces = False
+        breaks = False
+        start = end = 0
+        while end <= len(text):
+            ch = None
+            if end < len(text):
+                ch = text[end]
+            if breaks:
+                if ch is None or ch not in u'\n\x85\u2028\u2029':
+                    if not leading_space and ch is not None and ch != u' '  \
+                            and text[start] == u'\n':
+                        self.write_line_break()
+                    leading_space = (ch == u' ')
+                    for br in text[start:end]:
+                        if br == u'\n':
+                            self.write_line_break()
+                        else:
+                            self.write_line_break(br)
+                    if ch is not None:
+                        self.write_indent()
+                    start = end
+            elif spaces:
+                if ch != u' ':
+                    if start+1 == end and self.column > self.best_width:
+                        self.write_indent()
+                    else:
+                        data = text[start:end]
+                        self.column += len(data)
+                        if self.encoding:
+                            data = data.encode(self.encoding)
+                        self.stream.write(data)
+                    start = end
+            else:
+                if ch is None or ch in u' \n\x85\u2028\u2029':
+                    data = text[start:end]
+                    if self.encoding:
+                        data = data.encode(self.encoding)
+                    self.stream.write(data)
+                    if ch is None:
+                        self.write_line_break()
+                    start = end
+            if ch is not None:
+                breaks = (ch in u'\n\x85\u2028\u2029')
+                spaces = (ch == u' ')
+            end += 1
+
+    def write_literal(self, text):
+        chomp = self.determine_chomp(text)
+        self.write_indicator(u'|'+chomp, True)
+        self.write_indent()
+        breaks = False
+        start = end = 0
+        while end <= len(text):
+            ch = None
+            if end < len(text):
+                ch = text[end]
+            if breaks:
+                if ch is None or ch not in u'\n\x85\u2028\u2029':
+                    for br in text[start:end]:
+                        if br == u'\n':
+                            self.write_line_break()
+                        else:
+                            self.write_line_break(br)
+                    if ch is not None:
+                        self.write_indent()
+                    start = end
+            else:
+                if ch is None or ch in u'\n\x85\u2028\u2029':
+                    data = text[start:end]
+                    if self.encoding:
+                        data = data.encode(self.encoding)
+                    self.stream.write(data)
+                    if ch is None:
+                        self.write_line_break()
+                    start = end
+            if ch is not None:
+                breaks = (ch in u'\n\x85\u2028\u2029')
+            end += 1
+
+    def write_plain(self, text, split=True):
+        if not text:
+            return
+        if not self.whitespace:
+            data = u' '
+            self.column += len(data)
+            if self.encoding:
+                data = data.encode(self.encoding)
+            self.stream.write(data)
+        self.writespace = False
+        self.indention = False
+        spaces = False
+        breaks = False
+        start = end = 0
+        while end <= len(text):
+            ch = None
+            if end < len(text):
+                ch = text[end]
+            if spaces:
+                if ch != u' ':
+                    if start+1 == end and self.column > self.best_width and split:
+                        self.write_indent()
+                        self.writespace = False
+                        self.indention = False
+                    else:
+                        data = text[start:end]
+                        self.column += len(data)
+                        if self.encoding:
+                            data = data.encode(self.encoding)
+                        self.stream.write(data)
+                    start = end
+            elif breaks:
+                if ch not in u'\n\x85\u2028\u2029':
+                    if text[start] == u'\n':
+                        self.write_line_break()
+                    for br in text[start:end]:
+                        if br == u'\n':
+                            self.write_line_break()
+                        else:
+                            self.write_line_break(br)
+                    self.write_indent()
+                    self.whitespace = False
+                    self.indention = False
+                    start = end
+            else:
+                if ch is None or ch in u' \n\x85\u2028\u2029':
+                    data = text[start:end]
+                    self.column += len(data)
+                    if self.encoding:
+                        data = data.encode(self.encoding)
+                    self.stream.write(data)
+                    start = end
+            if ch is not None:
+                spaces = (ch == u' ')
+                breaks = (ch in u'\n\x85\u2028\u2029')
+            end += 1
+

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/emitter.pyc
----------------------------------------------------------------------
diff --git a/tools/bin/ext/yaml/emitter.pyc b/tools/bin/ext/yaml/emitter.pyc
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http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/error.py
----------------------------------------------------------------------
diff --git a/tools/bin/ext/yaml/error.py b/tools/bin/ext/yaml/error.py
new file mode 100644
index 0000000..577686d
--- /dev/null
+++ b/tools/bin/ext/yaml/error.py
@@ -0,0 +1,75 @@
+
+__all__ = ['Mark', 'YAMLError', 'MarkedYAMLError']
+
+class Mark(object):
+
+    def __init__(self, name, index, line, column, buffer, pointer):
+        self.name = name
+        self.index = index
+        self.line = line
+        self.column = column
+        self.buffer = buffer
+        self.pointer = pointer
+
+    def get_snippet(self, indent=4, max_length=75):
+        if self.buffer is None:
+            return None
+        head = ''
+        start = self.pointer
+        while start > 0 and self.buffer[start-1] not in u'\0\r\n\x85\u2028\u2029':
+            start -= 1
+            if self.pointer-start > max_length/2-1:
+                head = ' ... '
+                start += 5
+                break
+        tail = ''
+        end = self.pointer
+        while end < len(self.buffer) and self.buffer[end] not in u'\0\r\n\x85\u2028\u2029':
+            end += 1
+            if end-self.pointer > max_length/2-1:
+                tail = ' ... '
+                end -= 5
+                break
+        snippet = self.buffer[start:end].encode('utf-8')
+        return ' '*indent + head + snippet + tail + '\n'  \
+                + ' '*(indent+self.pointer-start+len(head)) + '^'
+
+    def __str__(self):
+        snippet = self.get_snippet()
+        where = "  in \"%s\", line %d, column %d"   \
+                % (self.name, self.line+1, self.column+1)
+        if snippet is not None:
+            where += ":\n"+snippet
+        return where
+
+class YAMLError(Exception):
+    pass
+
+class MarkedYAMLError(YAMLError):
+
+    def __init__(self, context=None, context_mark=None,
+            problem=None, problem_mark=None, note=None):
+        self.context = context
+        self.context_mark = context_mark
+        self.problem = problem
+        self.problem_mark = problem_mark
+        self.note = note
+
+    def __str__(self):
+        lines = []
+        if self.context is not None:
+            lines.append(self.context)
+        if self.context_mark is not None  \
+            and (self.problem is None or self.problem_mark is None
+                    or self.context_mark.name != self.problem_mark.name
+                    or self.context_mark.line != self.problem_mark.line
+                    or self.context_mark.column != self.problem_mark.column):
+            lines.append(str(self.context_mark))
+        if self.problem is not None:
+            lines.append(self.problem)
+        if self.problem_mark is not None:
+            lines.append(str(self.problem_mark))
+        if self.note is not None:
+            lines.append(self.note)
+        return '\n'.join(lines)
+

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/error.pyc
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diff --git a/tools/bin/ext/yaml/error.pyc b/tools/bin/ext/yaml/error.pyc
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http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/events.py
----------------------------------------------------------------------
diff --git a/tools/bin/ext/yaml/events.py b/tools/bin/ext/yaml/events.py
new file mode 100644
index 0000000..f79ad38
--- /dev/null
+++ b/tools/bin/ext/yaml/events.py
@@ -0,0 +1,86 @@
+
+# Abstract classes.
+
+class Event(object):
+    def __init__(self, start_mark=None, end_mark=None):
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+    def __repr__(self):
+        attributes = [key for key in ['anchor', 'tag', 'implicit', 'value']
+                if hasattr(self, key)]
+        arguments = ', '.join(['%s=%r' % (key, getattr(self, key))
+                for key in attributes])
+        return '%s(%s)' % (self.__class__.__name__, arguments)
+
+class NodeEvent(Event):
+    def __init__(self, anchor, start_mark=None, end_mark=None):
+        self.anchor = anchor
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+
+class CollectionStartEvent(NodeEvent):
+    def __init__(self, anchor, tag, implicit, start_mark=None, end_mark=None,
+            flow_style=None):
+        self.anchor = anchor
+        self.tag = tag
+        self.implicit = implicit
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.flow_style = flow_style
+
+class CollectionEndEvent(Event):
+    pass
+
+# Implementations.
+
+class StreamStartEvent(Event):
+    def __init__(self, start_mark=None, end_mark=None, encoding=None):
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.encoding = encoding
+
+class StreamEndEvent(Event):
+    pass
+
+class DocumentStartEvent(Event):
+    def __init__(self, start_mark=None, end_mark=None,
+            explicit=None, version=None, tags=None):
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.explicit = explicit
+        self.version = version
+        self.tags = tags
+
+class DocumentEndEvent(Event):
+    def __init__(self, start_mark=None, end_mark=None,
+            explicit=None):
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.explicit = explicit
+
+class AliasEvent(NodeEvent):
+    pass
+
+class ScalarEvent(NodeEvent):
+    def __init__(self, anchor, tag, implicit, value,
+            start_mark=None, end_mark=None, style=None):
+        self.anchor = anchor
+        self.tag = tag
+        self.implicit = implicit
+        self.value = value
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.style = style
+
+class SequenceStartEvent(CollectionStartEvent):
+    pass
+
+class SequenceEndEvent(CollectionEndEvent):
+    pass
+
+class MappingStartEvent(CollectionStartEvent):
+    pass
+
+class MappingEndEvent(CollectionEndEvent):
+    pass
+

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/events.pyc
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http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/loader.py
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diff --git a/tools/bin/ext/yaml/loader.py b/tools/bin/ext/yaml/loader.py
new file mode 100644
index 0000000..293ff46
--- /dev/null
+++ b/tools/bin/ext/yaml/loader.py
@@ -0,0 +1,40 @@
+
+__all__ = ['BaseLoader', 'SafeLoader', 'Loader']
+
+from reader import *
+from scanner import *
+from parser import *
+from composer import *
+from constructor import *
+from resolver import *
+
+class BaseLoader(Reader, Scanner, Parser, Composer, BaseConstructor, BaseResolver):
+
+    def __init__(self, stream):
+        Reader.__init__(self, stream)
+        Scanner.__init__(self)
+        Parser.__init__(self)
+        Composer.__init__(self)
+        BaseConstructor.__init__(self)
+        BaseResolver.__init__(self)
+
+class SafeLoader(Reader, Scanner, Parser, Composer, SafeConstructor, Resolver):
+
+    def __init__(self, stream):
+        Reader.__init__(self, stream)
+        Scanner.__init__(self)
+        Parser.__init__(self)
+        Composer.__init__(self)
+        SafeConstructor.__init__(self)
+        Resolver.__init__(self)
+
+class Loader(Reader, Scanner, Parser, Composer, Constructor, Resolver):
+
+    def __init__(self, stream):
+        Reader.__init__(self, stream)
+        Scanner.__init__(self)
+        Parser.__init__(self)
+        Composer.__init__(self)
+        Constructor.__init__(self)
+        Resolver.__init__(self)
+

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/loader.pyc
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http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/nodes.py
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diff --git a/tools/bin/ext/yaml/nodes.py b/tools/bin/ext/yaml/nodes.py
new file mode 100644
index 0000000..c4f070c
--- /dev/null
+++ b/tools/bin/ext/yaml/nodes.py
@@ -0,0 +1,49 @@
+
+class Node(object):
+    def __init__(self, tag, value, start_mark, end_mark):
+        self.tag = tag
+        self.value = value
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+    def __repr__(self):
+        value = self.value
+        #if isinstance(value, list):
+        #    if len(value) == 0:
+        #        value = '<empty>'
+        #    elif len(value) == 1:
+        #        value = '<1 item>'
+        #    else:
+        #        value = '<%d items>' % len(value)
+        #else:
+        #    if len(value) > 75:
+        #        value = repr(value[:70]+u' ... ')
+        #    else:
+        #        value = repr(value)
+        value = repr(value)
+        return '%s(tag=%r, value=%s)' % (self.__class__.__name__, self.tag, value)
+
+class ScalarNode(Node):
+    id = 'scalar'
+    def __init__(self, tag, value,
+            start_mark=None, end_mark=None, style=None):
+        self.tag = tag
+        self.value = value
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.style = style
+
+class CollectionNode(Node):
+    def __init__(self, tag, value,
+            start_mark=None, end_mark=None, flow_style=None):
+        self.tag = tag
+        self.value = value
+        self.start_mark = start_mark
+        self.end_mark = end_mark
+        self.flow_style = flow_style
+
+class SequenceNode(CollectionNode):
+    id = 'sequence'
+
+class MappingNode(CollectionNode):
+    id = 'mapping'
+

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/nodes.pyc
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http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/parser.py
----------------------------------------------------------------------
diff --git a/tools/bin/ext/yaml/parser.py b/tools/bin/ext/yaml/parser.py
new file mode 100644
index 0000000..a46bb9e
--- /dev/null
+++ b/tools/bin/ext/yaml/parser.py
@@ -0,0 +1,586 @@
+
+# The following YAML grammar is LL(1) and is parsed by a recursive descent
+# parser.
+#
+# stream            ::= STREAM-START implicit_document? explicit_document* STREAM-END
+# implicit_document ::= block_node DOCUMENT-END*
+# explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
+# block_node_or_indentless_sequence ::=
+#                       ALIAS
+#                       | properties (block_content | indentless_block_sequence)?
+#                       | block_content
+#                       | indentless_block_sequence
+# block_node        ::= ALIAS
+#                       | properties block_content?
+#                       | block_content
+# flow_node         ::= ALIAS
+#                       | properties flow_content?
+#                       | flow_content
+# properties        ::= TAG ANCHOR? | ANCHOR TAG?
+# block_content     ::= block_collection | flow_collection | SCALAR
+# flow_content      ::= flow_collection | SCALAR
+# block_collection  ::= block_sequence | block_mapping
+# flow_collection   ::= flow_sequence | flow_mapping
+# block_sequence    ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END
+# indentless_sequence   ::= (BLOCK-ENTRY block_node?)+
+# block_mapping     ::= BLOCK-MAPPING_START
+#                       ((KEY block_node_or_indentless_sequence?)?
+#                       (VALUE block_node_or_indentless_sequence?)?)*
+#                       BLOCK-END
+# flow_sequence     ::= FLOW-SEQUENCE-START
+#                       (flow_sequence_entry FLOW-ENTRY)*
+#                       flow_sequence_entry?
+#                       FLOW-SEQUENCE-END
+# flow_sequence_entry   ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+# flow_mapping      ::= FLOW-MAPPING-START
+#                       (flow_mapping_entry FLOW-ENTRY)*
+#                       flow_mapping_entry?
+#                       FLOW-MAPPING-END
+# flow_mapping_entry    ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+#
+# FIRST sets:
+#
+# stream: { STREAM-START }
+# explicit_document: { DIRECTIVE DOCUMENT-START }
+# implicit_document: FIRST(block_node)
+# block_node: { ALIAS TAG ANCHOR SCALAR BLOCK-SEQUENCE-START BLOCK-MAPPING-START FLOW-SEQUENCE-START FLOW-MAPPING-START }
+# flow_node: { ALIAS ANCHOR TAG SCALAR FLOW-SEQUENCE-START FLOW-MAPPING-START }
+# block_content: { BLOCK-SEQUENCE-START BLOCK-MAPPING-START FLOW-SEQUENCE-START FLOW-MAPPING-START SCALAR }
+# flow_content: { FLOW-SEQUENCE-START FLOW-MAPPING-START SCALAR }
+# block_collection: { BLOCK-SEQUENCE-START BLOCK-MAPPING-START }
+# flow_collection: { FLOW-SEQUENCE-START FLOW-MAPPING-START }
+# block_sequence: { BLOCK-SEQUENCE-START }
+# block_mapping: { BLOCK-MAPPING-START }
+# block_node_or_indentless_sequence: { ALIAS ANCHOR TAG SCALAR BLOCK-SEQUENCE-START BLOCK-MAPPING-START FLOW-SEQUENCE-START FLOW-MAPPING-START BLOCK-ENTRY }
+# indentless_sequence: { ENTRY }
+# flow_collection: { FLOW-SEQUENCE-START FLOW-MAPPING-START }
+# flow_sequence: { FLOW-SEQUENCE-START }
+# flow_mapping: { FLOW-MAPPING-START }
+# flow_sequence_entry: { ALIAS ANCHOR TAG SCALAR FLOW-SEQUENCE-START FLOW-MAPPING-START KEY }
+# flow_mapping_entry: { ALIAS ANCHOR TAG SCALAR FLOW-SEQUENCE-START FLOW-MAPPING-START KEY }
+
+__all__ = ['Parser', 'ParserError']
+
+from error import MarkedYAMLError
+from tokens import *
+from events import *
+from scanner import *
+
+class ParserError(MarkedYAMLError):
+    pass
+
+class Parser(object):
+    # Since writing a recursive-descendant parser is a straightforward task, we
+    # do not give many comments here.
+    # Note that we use Python generators. If you rewrite the parser in another
+    # language, you may replace all 'yield'-s with event handler calls.
+
+    DEFAULT_TAGS = {
+        u'!':   u'!',
+        u'!!':  u'tag:yaml.org,2002:',
+    }
+
+    def __init__(self):
+        self.current_event = None
+        self.yaml_version = None
+        self.tag_handles = {}
+        self.states = []
+        self.marks = []
+        self.state = self.parse_stream_start
+
+    def check_event(self, *choices):
+        # Check the type of the next event.
+        if self.current_event is None:
+            if self.state:
+                self.current_event = self.state()
+        if self.current_event is not None:
+            if not choices:
+                return True
+            for choice in choices:
+                if isinstance(self.current_event, choice):
+                    return True
+        return False
+
+    def peek_event(self):
+        # Get the next event.
+        if self.current_event is None:
+            if self.state:
+                self.current_event = self.state()
+        return self.current_event
+
+    def get_event(self):
+        # Get the next event and proceed further.
+        if self.current_event is None:
+            if self.state:
+                self.current_event = self.state()
+        value = self.current_event
+        self.current_event = None
+        return value
+
+    # stream    ::= STREAM-START implicit_document? explicit_document* STREAM-END
+    # implicit_document ::= block_node DOCUMENT-END*
+    # explicit_document ::= DIRECTIVE* DOCUMENT-START block_node? DOCUMENT-END*
+
+    def parse_stream_start(self):
+
+        # Parse the stream start.
+        token = self.get_token()
+        event = StreamStartEvent(token.start_mark, token.end_mark,
+                encoding=token.encoding)
+
+        # Prepare the next state.
+        self.state = self.parse_implicit_document_start
+
+        return event
+
+    def parse_implicit_document_start(self):
+
+        # Parse an implicit document.
+        if not self.check_token(DirectiveToken, DocumentStartToken,
+                StreamEndToken):
+            self.tag_handles = self.DEFAULT_TAGS
+            token = self.peek_token()
+            start_mark = end_mark = token.start_mark
+            event = DocumentStartEvent(start_mark, end_mark,
+                    explicit=False)
+
+            # Prepare the next state.
+            self.states.append(self.parse_document_end)
+            self.state = self.parse_block_node
+
+            return event
+
+        else:
+            return self.parse_document_start()
+
+    def parse_document_start(self):
+
+        # Parse any extra document end indicators.
+        while self.check_token(DocumentEndToken):
+            self.get_token()
+
+        # Parse an explicit document.
+        if not self.check_token(StreamEndToken):
+            token = self.peek_token()
+            start_mark = token.start_mark
+            version, tags = self.process_directives()
+            if not self.check_token(DocumentStartToken):
+                raise ParserError(None, None,
+                        "expected '<document start>', but found %r"
+                        % self.peek_token().id,
+                        self.peek_token().start_mark)
+            token = self.get_token()
+            end_mark = token.end_mark
+            event = DocumentStartEvent(start_mark, end_mark,
+                    explicit=True, version=version, tags=tags)
+            self.states.append(self.parse_document_end)
+            self.state = self.parse_document_content
+        else:
+            # Parse the end of the stream.
+            token = self.get_token()
+            event = StreamEndEvent(token.start_mark, token.end_mark)
+            assert not self.states
+            assert not self.marks
+            self.state = None
+        return event
+
+    def parse_document_end(self):
+
+        # Parse the document end.
+        token = self.peek_token()
+        start_mark = end_mark = token.start_mark
+        explicit = False
+        if self.check_token(DocumentEndToken):
+            token = self.get_token()
+            end_mark = token.end_mark
+            explicit = True
+        event = DocumentEndEvent(start_mark, end_mark,
+                explicit=explicit)
+
+        # Prepare the next state.
+        self.state = self.parse_document_start
+
+        return event
+
+    def parse_document_content(self):
+        if self.check_token(DirectiveToken,
+                DocumentStartToken, DocumentEndToken, StreamEndToken):
+            event = self.process_empty_scalar(self.peek_token().start_mark)
+            self.state = self.states.pop()
+            return event
+        else:
+            return self.parse_block_node()
+
+    def process_directives(self):
+        self.yaml_version = None
+        self.tag_handles = {}
+        while self.check_token(DirectiveToken):
+            token = self.get_token()
+            if token.name == u'YAML':
+                if self.yaml_version is not None:
+                    raise ParserError(None, None,
+                            "found duplicate YAML directive", token.start_mark)
+                major, minor = token.value
+                if major != 1:
+                    raise ParserError(None, None,
+                            "found incompatible YAML document (version 1.* is required)",
+                            token.start_mark)
+                self.yaml_version = token.value
+            elif token.name == u'TAG':
+                handle, prefix = token.value
+                if handle in self.tag_handles:
+                    raise ParserError(None, None,
+                            "duplicate tag handle %r" % handle.encode('utf-8'),
+                            token.start_mark)
+                self.tag_handles[handle] = prefix
+        if self.tag_handles:
+            value = self.yaml_version, self.tag_handles.copy()
+        else:
+            value = self.yaml_version, None
+        for key in self.DEFAULT_TAGS:
+            if key not in self.tag_handles:
+                self.tag_handles[key] = self.DEFAULT_TAGS[key]
+        return value
+
+    # block_node_or_indentless_sequence ::= ALIAS
+    #               | properties (block_content | indentless_block_sequence)?
+    #               | block_content
+    #               | indentless_block_sequence
+    # block_node    ::= ALIAS
+    #                   | properties block_content?
+    #                   | block_content
+    # flow_node     ::= ALIAS
+    #                   | properties flow_content?
+    #                   | flow_content
+    # properties    ::= TAG ANCHOR? | ANCHOR TAG?
+    # block_content     ::= block_collection | flow_collection | SCALAR
+    # flow_content      ::= flow_collection | SCALAR
+    # block_collection  ::= block_sequence | block_mapping
+    # flow_collection   ::= flow_sequence | flow_mapping
+
+    def parse_block_node(self):
+        return self.parse_node(block=True)
+
+    def parse_flow_node(self):
+        return self.parse_node()
+
+    def parse_block_node_or_indentless_sequence(self):
+        return self.parse_node(block=True, indentless_sequence=True)
+
+    def parse_node(self, block=False, indentless_sequence=False):
+        if self.check_token(AliasToken):
+            token = self.get_token()
+            event = AliasEvent(token.value, token.start_mark, token.end_mark)
+            self.state = self.states.pop()
+        else:
+            anchor = None
+            tag = None
+            start_mark = end_mark = tag_mark = None
+            if self.check_token(AnchorToken):
+                token = self.get_token()
+                start_mark = token.start_mark
+                end_mark = token.end_mark
+                anchor = token.value
+                if self.check_token(TagToken):
+                    token = self.get_token()
+                    tag_mark = token.start_mark
+                    end_mark = token.end_mark
+                    tag = token.value
+            elif self.check_token(TagToken):
+                token = self.get_token()
+                start_mark = tag_mark = token.start_mark
+                end_mark = token.end_mark
+                tag = token.value
+                if self.check_token(AnchorToken):
+                    token = self.get_token()
+                    end_mark = token.end_mark
+                    anchor = token.value
+            if tag is not None:
+                handle, suffix = tag
+                if handle is not None:
+                    if handle not in self.tag_handles:
+                        raise ParserError("while parsing a node", start_mark,
+                                "found undefined tag handle %r" % handle.encode('utf-8'),
+                                tag_mark)
+                    tag = self.tag_handles[handle]+suffix
+                else:
+                    tag = suffix
+            #if tag == u'!':
+            #    raise ParserError("while parsing a node", start_mark,
+            #            "found non-specific tag '!'", tag_mark,
+            #            "Please check 'http://pyyaml.org/wiki/YAMLNonSpecificTag' and share your opinion.")
+            if start_mark is None:
+                start_mark = end_mark = self.peek_token().start_mark
+            event = None
+            implicit = (tag is None or tag == u'!')
+            if indentless_sequence and self.check_token(BlockEntryToken):
+                end_mark = self.peek_token().end_mark
+                event = SequenceStartEvent(anchor, tag, implicit,
+                        start_mark, end_mark)
+                self.state = self.parse_indentless_sequence_entry
+            else:
+                if self.check_token(ScalarToken):
+                    token = self.get_token()
+                    end_mark = token.end_mark
+                    if (token.plain and tag is None) or tag == u'!':
+                        implicit = (True, False)
+                    elif tag is None:
+                        implicit = (False, True)
+                    else:
+                        implicit = (False, False)
+                    event = ScalarEvent(anchor, tag, implicit, token.value,
+                            start_mark, end_mark, style=token.style)
+                    self.state = self.states.pop()
+                elif self.check_token(FlowSequenceStartToken):
+                    end_mark = self.peek_token().end_mark
+                    event = SequenceStartEvent(anchor, tag, implicit,
+                            start_mark, end_mark, flow_style=True)
+                    self.state = self.parse_flow_sequence_first_entry
+                elif self.check_token(FlowMappingStartToken):
+                    end_mark = self.peek_token().end_mark
+                    event = MappingStartEvent(anchor, tag, implicit,
+                            start_mark, end_mark, flow_style=True)
+                    self.state = self.parse_flow_mapping_first_key
+                elif block and self.check_token(BlockSequenceStartToken):
+                    end_mark = self.peek_token().start_mark
+                    event = SequenceStartEvent(anchor, tag, implicit,
+                            start_mark, end_mark, flow_style=False)
+                    self.state = self.parse_block_sequence_first_entry
+                elif block and self.check_token(BlockMappingStartToken):
+                    end_mark = self.peek_token().start_mark
+                    event = MappingStartEvent(anchor, tag, implicit,
+                            start_mark, end_mark, flow_style=False)
+                    self.state = self.parse_block_mapping_first_key
+                elif anchor is not None or tag is not None:
+                    # Empty scalars are allowed even if a tag or an anchor is
+                    # specified.
+                    event = ScalarEvent(anchor, tag, (implicit, False), u'',
+                            start_mark, end_mark)
+                    self.state = self.states.pop()
+                else:
+                    if block:
+                        node = 'block'
+                    else:
+                        node = 'flow'
+                    token = self.peek_token()
+                    raise ParserError("while parsing a %s node" % node, start_mark,
+                            "expected the node content, but found %r" % token.id,
+                            token.start_mark)
+        return event
+
+    # block_sequence ::= BLOCK-SEQUENCE-START (BLOCK-ENTRY block_node?)* BLOCK-END
+
+    def parse_block_sequence_first_entry(self):
+        token = self.get_token()
+        self.marks.append(token.start_mark)
+        return self.parse_block_sequence_entry()
+
+    def parse_block_sequence_entry(self):
+        if self.check_token(BlockEntryToken):
+            token = self.get_token()
+            if not self.check_token(BlockEntryToken, BlockEndToken):
+                self.states.append(self.parse_block_sequence_entry)
+                return self.parse_block_node()
+            else:
+                self.state = self.parse_block_sequence_entry
+                return self.process_empty_scalar(token.end_mark)
+        if not self.check_token(BlockEndToken):
+            token = self.peek_token()
+            raise ParserError("while parsing a block collection", self.marks[-1],
+                    "expected <block end>, but found %r" % token.id, token.start_mark)
+        token = self.get_token()
+        event = SequenceEndEvent(token.start_mark, token.end_mark)
+        self.state = self.states.pop()
+        self.marks.pop()
+        return event
+
+    # indentless_sequence ::= (BLOCK-ENTRY block_node?)+
+
+    def parse_indentless_sequence_entry(self):
+        if self.check_token(BlockEntryToken):
+            token = self.get_token()
+            if not self.check_token(BlockEntryToken,
+                    KeyToken, ValueToken, BlockEndToken):
+                self.states.append(self.parse_indentless_sequence_entry)
+                return self.parse_block_node()
+            else:
+                self.state = self.parse_indentless_sequence_entry
+                return self.process_empty_scalar(token.end_mark)
+        token = self.peek_token()
+        event = SequenceEndEvent(token.start_mark, token.start_mark)
+        self.state = self.states.pop()
+        return event
+
+    # block_mapping     ::= BLOCK-MAPPING_START
+    #                       ((KEY block_node_or_indentless_sequence?)?
+    #                       (VALUE block_node_or_indentless_sequence?)?)*
+    #                       BLOCK-END
+
+    def parse_block_mapping_first_key(self):
+        token = self.get_token()
+        self.marks.append(token.start_mark)
+        return self.parse_block_mapping_key()
+
+    def parse_block_mapping_key(self):
+        if self.check_token(KeyToken):
+            token = self.get_token()
+            if not self.check_token(KeyToken, ValueToken, BlockEndToken):
+                self.states.append(self.parse_block_mapping_value)
+                return self.parse_block_node_or_indentless_sequence()
+            else:
+                self.state = self.parse_block_mapping_value
+                return self.process_empty_scalar(token.end_mark)
+        if not self.check_token(BlockEndToken):
+            token = self.peek_token()
+            raise ParserError("while parsing a block mapping", self.marks[-1],
+                    "expected <block end>, but found %r" % token.id, token.start_mark)
+        token = self.get_token()
+        event = MappingEndEvent(token.start_mark, token.end_mark)
+        self.state = self.states.pop()
+        self.marks.pop()
+        return event
+
+    def parse_block_mapping_value(self):
+        if self.check_token(ValueToken):
+            token = self.get_token()
+            if not self.check_token(KeyToken, ValueToken, BlockEndToken):
+                self.states.append(self.parse_block_mapping_key)
+                return self.parse_block_node_or_indentless_sequence()
+            else:
+                self.state = self.parse_block_mapping_key
+                return self.process_empty_scalar(token.end_mark)
+        else:
+            self.state = self.parse_block_mapping_key
+            token = self.peek_token()
+            return self.process_empty_scalar(token.start_mark)
+
+    # flow_sequence     ::= FLOW-SEQUENCE-START
+    #                       (flow_sequence_entry FLOW-ENTRY)*
+    #                       flow_sequence_entry?
+    #                       FLOW-SEQUENCE-END
+    # flow_sequence_entry   ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+    #
+    # Note that while production rules for both flow_sequence_entry and
+    # flow_mapping_entry are equal, their interpretations are different.
+    # For `flow_sequence_entry`, the part `KEY flow_node? (VALUE flow_node?)?`
+    # generate an inline mapping (set syntax).
+
+    def parse_flow_sequence_first_entry(self):
+        token = self.get_token()
+        self.marks.append(token.start_mark)
+        return self.parse_flow_sequence_entry(first=True)
+
+    def parse_flow_sequence_entry(self, first=False):
+        if not self.check_token(FlowSequenceEndToken):
+            if not first:
+                if self.check_token(FlowEntryToken):
+                    self.get_token()
+                else:
+                    token = self.peek_token()
+                    raise ParserError("while parsing a flow sequence", self.marks[-1],
+                            "expected ',' or ']', but got %r" % token.id, token.start_mark)
+            
+            if self.check_token(KeyToken):
+                token = self.peek_token()
+                event = MappingStartEvent(None, None, True,
+                        token.start_mark, token.end_mark,
+                        flow_style=True)
+                self.state = self.parse_flow_sequence_entry_mapping_key
+                return event
+            elif not self.check_token(FlowSequenceEndToken):
+                self.states.append(self.parse_flow_sequence_entry)
+                return self.parse_flow_node()
+        token = self.get_token()
+        event = SequenceEndEvent(token.start_mark, token.end_mark)
+        self.state = self.states.pop()
+        self.marks.pop()
+        return event
+
+    def parse_flow_sequence_entry_mapping_key(self):
+        token = self.get_token()
+        if not self.check_token(ValueToken,
+                FlowEntryToken, FlowSequenceEndToken):
+            self.states.append(self.parse_flow_sequence_entry_mapping_value)
+            return self.parse_flow_node()
+        else:
+            self.state = self.parse_flow_sequence_entry_mapping_value
+            return self.process_empty_scalar(token.end_mark)
+
+    def parse_flow_sequence_entry_mapping_value(self):
+        if self.check_token(ValueToken):
+            token = self.get_token()
+            if not self.check_token(FlowEntryToken, FlowSequenceEndToken):
+                self.states.append(self.parse_flow_sequence_entry_mapping_end)
+                return self.parse_flow_node()
+            else:
+                self.state = self.parse_flow_sequence_entry_mapping_end
+                return self.process_empty_scalar(token.end_mark)
+        else:
+            self.state = self.parse_flow_sequence_entry_mapping_end
+            token = self.peek_token()
+            return self.process_empty_scalar(token.start_mark)
+
+    def parse_flow_sequence_entry_mapping_end(self):
+        self.state = self.parse_flow_sequence_entry
+        token = self.peek_token()
+        return MappingEndEvent(token.start_mark, token.start_mark)
+
+    # flow_mapping  ::= FLOW-MAPPING-START
+    #                   (flow_mapping_entry FLOW-ENTRY)*
+    #                   flow_mapping_entry?
+    #                   FLOW-MAPPING-END
+    # flow_mapping_entry    ::= flow_node | KEY flow_node? (VALUE flow_node?)?
+
+    def parse_flow_mapping_first_key(self):
+        token = self.get_token()
+        self.marks.append(token.start_mark)
+        return self.parse_flow_mapping_key(first=True)
+
+    def parse_flow_mapping_key(self, first=False):
+        if not self.check_token(FlowMappingEndToken):
+            if not first:
+                if self.check_token(FlowEntryToken):
+                    self.get_token()
+                else:
+                    token = self.peek_token()
+                    raise ParserError("while parsing a flow mapping", self.marks[-1],
+                            "expected ',' or '}', but got %r" % token.id, token.start_mark)
+            if self.check_token(KeyToken):
+                token = self.get_token()
+                if not self.check_token(ValueToken,
+                        FlowEntryToken, FlowMappingEndToken):
+                    self.states.append(self.parse_flow_mapping_value)
+                    return self.parse_flow_node()
+                else:
+                    self.state = self.parse_flow_mapping_value
+                    return self.process_empty_scalar(token.end_mark)
+            elif not self.check_token(FlowMappingEndToken):
+                self.states.append(self.parse_flow_mapping_empty_value)
+                return self.parse_flow_node()
+        token = self.get_token()
+        event = MappingEndEvent(token.start_mark, token.end_mark)
+        self.state = self.states.pop()
+        self.marks.pop()
+        return event
+
+    def parse_flow_mapping_value(self):
+        if self.check_token(ValueToken):
+            token = self.get_token()
+            if not self.check_token(FlowEntryToken, FlowMappingEndToken):
+                self.states.append(self.parse_flow_mapping_key)
+                return self.parse_flow_node()
+            else:
+                self.state = self.parse_flow_mapping_key
+                return self.process_empty_scalar(token.end_mark)
+        else:
+            self.state = self.parse_flow_mapping_key
+            token = self.peek_token()
+            return self.process_empty_scalar(token.start_mark)
+
+    def parse_flow_mapping_empty_value(self):
+        self.state = self.parse_flow_mapping_key
+        return self.process_empty_scalar(self.peek_token().start_mark)
+
+    def process_empty_scalar(self, mark):
+        return ScalarEvent(None, None, (True, False), u'', mark, mark)
+

http://git-wip-us.apache.org/repos/asf/incubator-hawq/blob/a485be47/tools/bin/ext/yaml/parser.pyc
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