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diff --git a/tensorflow/python/autograph/pyct/compiler.py b/tensorflow/python/autograph/pyct/compiler.py
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+++ b/tensorflow/python/autograph/pyct/compiler.py
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+# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# ==============================================================================
+"""Converting AST to code.
+
+Adapted from Tangent.
+"""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+# TODO(mdan): Use six for compatibility here.
+import atexit
+import imp
+import os
+import tempfile
+
+import astor
+import gast
+
+from tensorflow.python.autograph.pyct import origin_info
+
+
+def ast_to_source(node, indentation='  '):
+  """Return the source code of given AST.
+
+  Args:
+    node: The code to compile, as an AST object.
+    indentation: The string to use for indentation.
+
+  Returns:
+    code: The source code generated from the AST object
+    source_mapping: A mapping between the user and AutoGraph generated code.
+  """
+  if not isinstance(node, (list, tuple)):
+    node = (node,)
+  generator = astor.codegen.SourceGenerator(indentation, False,
+                                            astor.string_repr.pretty_string)
+
+  for n in node:
+    if isinstance(n, gast.AST):
+      n = gast.gast_to_ast(n)
+    generator.visit(n)
+    generator.result.append('\n')
+
+  # In some versions of Python, literals may appear as actual values. This
+  # ensures everything is string.
+  code = map(str, generator.result)
+  code = astor.source_repr.pretty_source(code).lstrip()
+
+  return code
+
+
+def ast_to_object(nodes,
+                  indentation='  ',
+                  include_source_map=False,
+                  source_prefix=None,
+                  delete_on_exit=True):
+  """Return the Python objects represented by given AST.
+
+  Compiling the AST code this way ensures that the source code is readable by
+  e.g. `pdb` or `inspect`.
+
+  Args:
+    nodes: Union[ast.AST, Iterable[ast.AST]], the code to compile, as an AST
+        object.
+    indentation: Text, the string to use for indentation.
+    include_source_map: bool, whether to attach a source map to the compiled
+        object. Also see origin_info.py.
+    source_prefix: Optional[Text], string to print as-is into the source file.
+    delete_on_exit: bool, whether to delete the temporary file used for
+        compilation on exit.
+
+  Returns:
+    compiled_nodes: A module object containing the compiled source code.
+    source: The source code of the compiled object
+  Raises:
+    ValueError: If ag_source_map__ is already in the namespace of the compiled
+    nodes.
+  """
+  if not isinstance(nodes, (list, tuple)):
+    nodes = (nodes,)
+
+  source = ast_to_source(nodes, indentation=indentation)
+
+  if source_prefix:
+    source = source_prefix + '\n' + source
+
+  with tempfile.NamedTemporaryFile(mode='w', suffix='.py', delete=False) as f:
+    module_name = os.path.basename(f.name[:-3])
+    f.write(source)
+
+    if isinstance(nodes, (list, tuple)):
+      indices = range(-len(nodes), 0)
+    else:
+      indices = (-1,)
+
+    if include_source_map:
+      source_map = origin_info.source_map(nodes, source, f.name, indices)
+
+  # TODO(mdan): Try flush() and delete=False instead.
+  if delete_on_exit:
+    atexit.register(lambda: os.remove(f.name))
+  compiled_nodes = imp.load_source(module_name, f.name)
+
+  # TODO(znado): Clean this up so we don't need to attach it to the namespace.
+  # TODO(znado): This does not work for classes because their methods share a
+  # namespace.
+  # This attaches the source map which is needed for error handling.  Note that
+  # api.to_graph copies this source map into an attribute of the function.
+  #
+  # We need this so the ag_source_map__ variable is available to the call to
+  # rewrite_graph_construction_error in the except block inside each function
+  # that handles graph construction errors.
+  #
+  # We cannot get the rewritten function name until it is too late so templating
+  # is hard, and this cleanly fixes the
+  # issues encountered with nested functions because this is attached to the
+  # outermost one.
+  if include_source_map:
+    # TODO(mdan): This name should be decided by the caller.
+    source_map_name = 'ag_source_map__'
+    if source_map_name in compiled_nodes.__dict__:
+      raise ValueError('cannot convert %s because is has namespace attribute '
+                       '"%s", which is reserved for AutoGraph.' %
+                       (compiled_nodes, source_map_name))
+    compiled_nodes.__dict__[source_map_name] = source_map
+
+  return compiled_nodes, source