code: def is_tpu_strategy(strategy):
      """Returns whether the strategy is a TPU strategy."""
      return isinstance(
          strategy,
          (
              tpu_strategy.TPUStrategy,
              tpu_strategy.TPUStrategyV1,
              tpu_strategy.TPUStrategyV2,
          ),
      )
  
imports: import collections
  import dataclasses
  import functools
  import io
  import itertools
  import threading
  from absl import app
  from tensorflow.python.compat import v2_compat
  from tensorflow.python.distribute import collective_all_reduce_strategy
  from tensorflow.python.distribute import multi_process_runner
  from tensorflow.python.distribute import multi_worker_test_base
  from tensorflow.python.distribute import tpu_strategy
  from tensorflow.python.distribute import values
  from tensorflow.python.eager import context
  from tensorflow.python.framework import config
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import tensor
  from tensorflow.python.ops import array_ops
  from tensorflow.python.ops import array_ops_stack
  from tensorflow.python.util import nest
label_desc: Use image node_id 15 for calling a global function with example usage: is_tpu_strategy(strategy) and returns: isinstance