class_docstr: Program definition for D4PG.
code: def counter(self):
      return tf2_savers.CheckpointingRunner(
          counting.Counter(),
          time_delta_minutes=1,
          subdirectory="counter",
      )
  
imports: import copy
  from typing import Callable, Dict, Optional
  import acme
  from acme import specs
  from acme.agents.tf.d4pg import agent
  from acme.tf import savers
  from acme.utils import counting
  from acme.utils import loggers
  from acme.utils import lp_utils
  import dm_env
  import launchpad
  import reverb
  import sonnet
  import tensorflow
label_desc: Use image node_id 3 for calling the DistributedD4PG obj's underlying member method code with example usage: obj.counter() and returns: tf2_savers