Adding cython v0.20.2 in third-party.

third_party/cython/src/Cython/Debugger/DebugWriter.py

Index: third_party/cython/src/Cython/Debugger/DebugWriter.py
diff --git a/third_party/cython/src/Cython/Debugger/DebugWriter.py b/third_party/cython/src/Cython/Debugger/DebugWriter.py
new file mode 100644
index 0000000000000000000000000000000000000000..7242a582ed6e3add6be064b0c11d416fe0553b22
--- /dev/null
+++ b/third_party/cython/src/Cython/Debugger/DebugWriter.py
@@ -0,0 +1,78 @@
+from __future__ import with_statement
+
+import os
+import sys
+import errno
+
+try:
+  from lxml import etree
+  have_lxml = True
+except ImportError:
+    have_lxml = False
+    try:
+        # Python 2.5
+        from xml.etree import cElementTree as etree
+    except ImportError:
+        try:
+            # Python 2.5
+            from xml.etree import ElementTree as etree
+        except ImportError:
+            try:
+                # normal cElementTree install
+                import cElementTree as etree
+            except ImportError:
+                try:
+                    # normal ElementTree install
+                    import elementtree.ElementTree as etree
+                except ImportError:
+                    etree = None
+
+from Cython.Compiler import Errors
+
+
+class CythonDebugWriter(object):
+    """
+    Class to output debugging information for cygdb
+
+    It writes debug information to cython_debug/cython_debug_info_<modulename>
+    in the build directory.
+    """
+
+    def __init__(self, output_dir):
+        if etree is None:
+            raise Errors.NoElementTreeInstalledException()
+
+        self.output_dir = os.path.join(output_dir, 'cython_debug')
+        self.tb = etree.TreeBuilder()
+        # set by Cython.Compiler.ParseTreeTransforms.DebugTransform
+        self.module_name = None
+        self.start('cython_debug', attrs=dict(version='1.0'))
+
+    def start(self, name, attrs=None):
+        self.tb.start(name, attrs or {})
+
+    def end(self, name):
+        self.tb.end(name)
+
+    def serialize(self):
+        self.tb.end('Module')
+        self.tb.end('cython_debug')
+        xml_root_element = self.tb.close()
+
+        try:
+            os.makedirs(self.output_dir)
+        except OSError, e:
+            if e.errno != errno.EEXIST:
+                raise
+
+        et = etree.ElementTree(xml_root_element)
+        kw = {}
+        if have_lxml:
+            kw['pretty_print'] = True
+
+        fn = "cython_debug_info_" + self.module_name
+        et.write(os.path.join(self.output_dir, fn), encoding="UTF-8", **kw)
+
+        interpreter_path = os.path.join(self.output_dir, 'interpreter')
+        with open(interpreter_path, 'w') as f:
+            f.write(sys.executable)