message: Enable error interpolation in Python.
  It is still guarded by an experimental config setting and can be enabled using e.g.
  config = tf.ConfigProto()
  config.experimental.client_handles_error_formatting = True
  with tf.Session(config=config) as sess:
  ...
diff: @@ -29,6 +29,7 @@ import numpy as np
  from tensorflow.core.protobuf import config_pb2
  from tensorflow.python import pywrap_tensorflow as tf_session
  from tensorflow.python.framework import device
  +from tensorflow.python.framework import error_interpolation
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import sparse_tensor
  @@ -1301,6 +1302,9 @@ class BaseSession(SessionInterface):
  node_def = op.node_def
  except KeyError:
  pass
  + if (self._config is not None and
  + self._config.experimental.client_handles_error_formatting):
  + message = error_interpolation.interpolate(message, self._graph)
  raise type(e)(node_def, op, message)
  def _extend_graph(self):
  