code: def default_evaluator_factory(
      environment_factory: types.EnvironmentFactory,
      network_factory: NetworkFactory[builders.Networks],
      policy_factory: PolicyFactory[builders.Networks, builders.Policy],
      logger_factory: loggers.LoggerFactory,
      observers: Sequence[observers_lib.EnvLoopObserver] = (),
  ) -> EvaluatorFactory[builders.Policy]:
      """Returns a default evaluator process."""
  
      def evaluator(
          random_key: types.PRNGKey,
          variable_source: core.VariableSource,
          counter: counting.Counter,
          make_actor: MakeActorFn[builders.Policy],
      ):
          """The evaluation process."""
  
          # Create environment and evaluator networks
          environment_key, actor_key = jax.random.split(random_key)
          # Environments normally require uint32 as a seed.
          environment = environment_factory(
              utils.sample_uint32(environment_key)
          )
          environment_spec = specs.make_environment_spec(environment)
          networks = network_factory(environment_spec)
          policy = policy_factory(networks, environment_spec, True)
          actor = make_actor(
              actor_key, policy, environment_spec, variable_source
          )
  
          # Create logger and counter.
          counter = counting.Counter(counter, "evaluator")
          logger = logger_factory("evaluator", "actor_steps", 0)
  
          # Create the run loop and return it.
          return environment_loop.EnvironmentLoop(
              environment, actor, counter, logger, observers=observers
          )
  
      return evaluator
  
imports: import dataclasses
  import datetime
  from typing import Any, Callable, Dict, Generic, Iterator, Optional, Sequence
  from acme import core
  from acme import environment_loop
  from acme import specs
  from acme.agents.jax import builders
  from acme.jax import types
  from acme.jax import utils
  from acme.utils import counting
  from acme.utils import loggers
  from acme.utils import observers
  from acme.utils import experiment_utils
  import jax
  from typing_extensions import Protocol
label_desc: Use image node_id 1 for calling a global function with example usage: default_evaluator_factory(environment_factory, network_factory, policy_factory, logger_factory, observers) and returns: evaluator, environment_loop