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diff --git a/tensorflow/python/framework/traceable_stack.py b/tensorflow/python/framework/traceable_stack.py
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+++ b/tensorflow/python/framework/traceable_stack.py
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+# Copyright 2015 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.
+# ==============================================================================
+"""A simple stack that associates filename and line numbers with each object."""
+
+from __future__ import absolute_import
+from __future__ import division
+from __future__ import print_function
+
+from tensorflow.python.util import tf_stack
+
+
+class TraceableObject(object):
+  """Wrap an object together with its the code definition location."""
+
+  # Return codes for the set_filename_and_line_from_caller() method.
+  SUCCESS, HEURISTIC_USED, FAILURE = (0, 1, 2)
+
+  def __init__(self, obj, filename=None, lineno=None):
+    self.obj = obj
+    self.filename = filename
+    self.lineno = lineno
+
+  def set_filename_and_line_from_caller(self, offset=0):
+    """Set filename and line using the caller's stack frame.
+
+    If the requested stack information is not available, a heuristic may
+    be applied and self.HEURISTIC USED will be returned.  If the heuristic
+    fails then no change will be made to the filename and lineno members
+    (None by default) and self.FAILURE will be returned.
+
+    Args:
+      offset: Integer.  If 0, the caller's stack frame is used.  If 1,
+          the caller's caller's stack frame is used.  Larger values are
+          permissible but if out-of-range (larger than the number of stack
+          frames available) the outermost stack frame will be used.
+
+    Returns:
+      TraceableObject.SUCCESS if appropriate stack information was found,
+      TraceableObject.HEURISTIC_USED if the offset was larger than the stack,
+      and TraceableObject.FAILURE if the stack was empty.
+    """
+    # Offset is defined in "Args" as relative to the caller.  We are one frame
+    # beyond the caller.
+    local_offset = offset + 1
+
+    frame_records = tf_stack.extract_stack()
+    if not frame_records:
+      return self.FAILURE
+    if len(frame_records) >= local_offset:
+      # Negative indexing is one-indexed instead of zero-indexed.
+      negative_offset = -(local_offset + 1)
+      self.filename, self.lineno = frame_records[negative_offset][:2]
+      return self.SUCCESS
+    else:
+      # If the offset is too large then we use the largest offset possible,
+      # meaning we use the outermost stack frame at index 0.
+      self.filename, self.lineno = frame_records[0][:2]
+      return self.HEURISTIC_USED
+
+  def copy_metadata(self):
+    """Return a TraceableObject like this one, but without the object."""
+    return self.__class__(None, filename=self.filename, lineno=self.lineno)
+
+
+class TraceableStack(object):
+  """A stack of TraceableObjects."""
+
+  def __init__(self, existing_stack=None):
+    """Constructor.
+
+    Args:
+      existing_stack: [TraceableObject, ...] If provided, this object will
+        set its new stack to a SHALLOW COPY of existing_stack.
+    """
+    self._stack = existing_stack[:] if existing_stack else []
+
+  def push_obj(self, obj, offset=0):
+    """Add object to the stack and record its filename and line information.
+
+    Args:
+      obj: An object to store on the stack.
+      offset: Integer.  If 0, the caller's stack frame is used.  If 1,
+          the caller's caller's stack frame is used.
+
+    Returns:
+      TraceableObject.SUCCESS if appropriate stack information was found,
+      TraceableObject.HEURISTIC_USED if the stack was smaller than expected,
+      and TraceableObject.FAILURE if the stack was empty.
+    """
+    traceable_obj = TraceableObject(obj)
+    self._stack.append(traceable_obj)
+    # Offset is defined in "Args" as relative to the caller.  We are 1 frame
+    # beyond the caller and need to compensate.
+    return traceable_obj.set_filename_and_line_from_caller(offset + 1)
+
+  def pop_obj(self):
+    """Remove last-inserted object and return it, without filename/line info."""
+    return self._stack.pop().obj
+
+  def peek_objs(self):
+    """Return list of stored objects ordered newest to oldest."""
+    return [t_obj.obj for t_obj in reversed(self._stack)]
+
+  def peek_traceable_objs(self):
+    """Return list of stored TraceableObjects ordered newest to oldest."""
+    return list(reversed(self._stack))
+
+  def __len__(self):
+    """Return number of items on the stack, and used for truth-value testing."""
+    return len(self._stack)
+
+  def copy(self):
+    """Return a copy of self referencing the same objects but in a new list.
+
+    This method is implemented to support thread-local stacks.
+
+    Returns:
+      TraceableStack with a new list that holds existing objects.
+    """
+    return TraceableStack(self._stack)