message: Add use of ObjectIdentitySet for tensor equality
diff: @@ -36,6 +36,7 @@ from tensorflow.python.ops import variable_scope
  from tensorflow.python.platform import tf_logging as logging
  from tensorflow.python.training.tracking import data_structures
  from tensorflow.python.util import nest
  +from tensorflow.python.util import object_identity
  from tensorflow.python.util.tf_export import tf_export
  @@ -150,7 +151,8 @@ def _lift_unlifted_variables(graph, variable_holder):
  ops.GraphKeys.GLOBAL_VARIABLES)
  local_collection_variables = ops.get_collection(
  ops.GraphKeys.LOCAL_VARIABLES)
  - existing_captures = set(graph.internal_captures)
  + existing_captures = object_identity.ObjectIdentitySet(
  + graph.internal_captures)
  lifted_variables = {}
  def _should_lift_variable(v):
  @@ -249,7 +251,8 @@ class WrappedFunction(function.ConcreteFunction):
  # Ignoring all feeds that are captures allows prune to be called
  # using wrapped_func.inputs even when it uses variables
  - internal_captures = self.graph.internal_captures
  + internal_captures = object_identity.ObjectIdentitySet(
  + self.graph.internal_captures)
  flat_feeds = [f for f in flat_feeds if f not in internal_captures]
  operation_fetches = []
  @@ -302,7 +305,7 @@ class WrappedFunction(function.ConcreteFunction):
  lift_map = lift_to_graph.lift_to_graph(
  operation_fetches + tensor_fetches,
  pruned_graph,
  - sources=flat_feeds + internal_captures)
  + sources=flat_feeds + self.graph.internal_captures)
  # Note that we add the component tensors of any composite tensors to the
  # returned function's outputs list; the list must contain these component
  