message: Avoid use of ObjectIdentitySet
diff: @@ -1550,16 +1550,16 @@ class ConcreteFunction(object):
  resource_variable_ops.variable_accessed(v)
  tensor_inputs = []
  - variables_used = object_identity.ObjectIdentitySet([])
  + variables_used = set([])
  for i, arg in enumerate(args):
  if isinstance(arg, resource_variable_ops.BaseResourceVariable):
  # We can pass a variable more than once, and in this case we need to
  # pass its handle only once.
  - if arg.handle in variables_used:
  + if id(arg.handle) in variables_used:
  continue
  resource_variable_ops.variable_accessed(arg)
  tensor_inputs.append(arg.handle)
  - variables_used.add(arg.handle)
  + variables_used.add(id(arg.handle))
  elif isinstance(arg, ops.Tensor):
  tensor_inputs.append(arg)
  if not executing_eagerly:
  