message: Added the Code Example for `VariableSynchronization`.
  Fixes
diff: @@ -83,6 +83,12 @@ class VariableSynchronization(enum.Enum):
  * `ON_READ`: Indicates that the variable will be aggregated across devices
  when it is read (eg. when checkpointing or when evaluating an op that uses
  the variable).
  +
  + Example:
  + >>> temp_grad=[tf.Variable([0.], trainable=False,
  + ... synchronization=tf.VariableSynchronization.ON_READ,
  + ... aggregation=tf.VariableAggregation.MEAN
  + ... )]
  """
  AUTO = 0
  NONE = 1
  