code: def testSimpleNetwork(self):
      # Create a wrapped network.
      wrapped_network = WrappedNetwork()
  
      # Create a splitter network which drops the mask (`passthrough_mask=False`).
      splitter_network = mask_splitter_network.MaskSplitterNetwork(
          splitter_fn=self._splitter_fn, wrapped_network=wrapped_network
      )
  
      # Apply splitter network which returns the `observation` and `mask` received
      # by the `wrapped_network`.
      (observation, mask), _ = splitter_network(
          self._observation_and_mask
      )
  
      # Check if the wrapped network received the observation part of the input.
      self.assertAllClose(
          observation, self._observation_and_mask["observation"]
      )
      # The wrapped network should *not* receive mask since the value of
      # `passthrough_mask=False` in the `splitter_network`.
      self.assertIsNone(mask)
  
imports: import tensorflow.compat.v2
  import tensorflow_probability
  from tf_agents.networks import mask_splitter_network
  from tf_agents.networks import network
  from tf_agents.networks import value_network
  from tf_agents.specs import distribution_spec
  from tf_agents.specs import tensor_spec
  from tf_agents.utils import test_utils
label_desc: Use image node_id 2 for calling the MaskSplitterNetworkTest obj's underlying member method code with example usage: obj.testSimpleNetwork() without return types