message: Use is_resource_variable() in train.assert_gloabl_step.
diff: @@ -18,7 +18,6 @@ from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  -
  from tensorflow.python.eager import context
  from tensorflow.python.framework import dtypes
  from tensorflow.python.framework import graph_io
  @@ -31,7 +30,6 @@ from tensorflow.python.ops import variables
  from tensorflow.python.platform import tf_logging as logging
  from tensorflow.python.util.tf_export import tf_export
  -
  # Picked a long key value to minimize the chance of collision with user defined
  # collection keys.
  GLOBAL_STEP_READ_KEY = 'global_step_read_op_cache'
  @@ -170,8 +168,7 @@ def assert_global_step(global_step_tensor):
  """
  if not (isinstance(global_step_tensor, variables.Variable) or
  isinstance(global_step_tensor, ops.Tensor) or
  - isinstance(global_step_tensor,
  - resource_variable_ops.ResourceVariable)):
  + resource_variable_ops.is_resource_variable(global_step_tensor)):
  raise TypeError(
  'Existing "global_step" must be a Variable or Tensor: %s.' %
  global_step_tensor)
  