class_docstr: Manages state and performs updates for IMPALA learner.
code: def params_for_actor(self) -> tuple[int, hk.Params]:
      return self._params_for_actor
  
imports: import functools
  import itertools
  import queue
  import threading
  import warnings
  import dm_env
  import haiku
  from examples.impala import agent
  from examples.impala import util
  import jax
  from jax.example_libraries import optimizers
  import jax.numpy
  import numpy
  import optax
  import rlax
label_desc: Use image node_id 5 for calling the Learner obj's underlying member method code with example usage: obj.params_for_actor() and returns: self