message: Fix how lists are instantiated
diff: @@ -1072,7 +1072,7 @@ class TPUFunction(object):
  # `execute op` replicates `_model_fn` `num_replicas` times, with each shard
  # running on a different logical core.
  compile_op, execute_op = tpu.split_compile_and_replicate(
  - _model_fn, inputs=[[]] * self._tpu_assignment.num_towers)
  + _model_fn, inputs=[[] for _ in range(self._tpu_assignment.num_towers)])
  # Generate CPU side operations to enqueue features/labels and dequeue
  # outputs from the model call.
  @@ -1217,7 +1217,7 @@ class TPUFunction(object):
  """
  # TODO(xiejw): Decide how to reduce outputs, or discard all but first.
  if self.execution_mode == model_fn_lib.ModeKeys.PREDICT:
  - outputs = [[]] * len(self._outfeed_spec)
  + outputs = [[] for _ in range(len(self._outfeed_spec))]
  outputs_per_replica = len(self._outfeed_spec)
  for i in range(self._tpu_assignment.num_towers):
  