code: def global_policy():
      """Returns the global dtype policy.
  
      The global policy is the default `tf.keras.mixed_precision.Policy` used for
      layers, if no policy is passed to the layer constructor. If no policy has been
      set with `keras.mixed_precision.set_global_policy`, this will return a policy
      constructed from `tf.keras.backend.floatx()` (floatx defaults to float32).
  
      >>> tf.keras.mixed_precision.global_policy()
      <Policy "float32">
      >>> tf.keras.layers.Dense(10).dtype_policy  # Defaults to the global policy
      <Policy "float32">
  
      If TensorFlow 2 behavior has been disabled with
      `tf.compat.v1.disable_v2_behavior()`, this will instead return a special
      "_infer" policy which infers the dtype from the dtype of the first input the
      first time the layer is called. This behavior matches the behavior that
      existed in TensorFlow 1.
  
      See `tf.keras.mixed_precision.Policy` for more information on policies.
  
      Returns:
        The global Policy.
      """
      if _global_policy is None:
          if base_layer_utils.v2_dtype_behavior_enabled():
              return Policy(backend.floatx())
          else:
              return Policy("_infer")
      return _global_policy
  
imports: import contextlib
  from tensorflow.python.framework import dtypes
  from tensorflow.python.keras import backend
  from tensorflow.python.keras.engine import base_layer_utils
  from tensorflow.python.keras.mixed_precision import device_compatibility_check
  from tensorflow.python.keras.mixed_precision import loss_scale
  from tensorflow.python.keras.utils import generic_utils
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.training.experimental import mixed_precision_global_state
label_desc: Use image node_id 1 for calling a global function with example usage: global_policy() and returns: _global_policy, Policy, Policy