class_docstr: D4PG Builder.
class_docstr_tok: ["D4PG","Builder","."]
code: def make_actor(
      self,
      random_key: networks_lib.PRNGKey,
      policy: actor_core_lib.ActorCore,
      environment_spec: specs.EnvironmentSpec,
      variable_source: Optional[core.VariableSource] = None,
      adder: Optional[adders.Adder] = None,
  ) -> acme.Actor:
      del environment_spec
      assert variable_source is not None
      # Inference happens on CPU, so it's better to move variables there too.
      variable_client = variable_utils.VariableClient(
          variable_source, "policy", device="cpu"
      )
      return actors.GenericActor(
          policy, random_key, variable_client, adder, backend="cpu"
      )
  
imports: from typing import Iterator, List, Optional
  import acme
  from acme import adders
  from acme import core
  from acme import specs
  from acme.adders import reverb
  from acme.adders.reverb import base
  from acme.agents.jax import actor_core
  from acme.agents.jax import actors
  from acme.agents.jax import builders
  from acme.agents.jax.d4pg import config
  from acme.agents.jax.d4pg import learning
  from acme.agents.jax.d4pg import networks
  from acme.datasets import reverb
  from acme.jax import networks
  from acme.jax import utils
  from acme.jax import variable_utils
  from acme.utils import counting
  from acme.utils import loggers
  import jax
  import optax
  import reverb
  from reverb import rate_limiters
  from reverb import structured_writer
label_desc: Use image node_id 6 for calling the D4PGBuilder obj's underlying member method code with example usage: obj.make_actor(random_key, policy, environment_spec, variable_source, adder) and returns: actors