code: def build(self) -> None:
      super().build()
  
      # Dict mapping module IDs to the respective entropy Scheduler instance.
      self.entropy_coeff_schedulers_per_module: Dict[
          ModuleID, Scheduler
      ] = LambdaDefaultDict(
          lambda module_id: Scheduler(
              fixed_value_or_schedule=(
                  self.config.get_config_for_module(
                      module_id
                  ).entropy_coeff
              ),
              framework=self.framework,
              device=self._device,
          )
      )
  
file_path: ray/python/ray/rllib/algorithms/impala/impala_learner.py
imports: from typing import Any, Dict
  from ray.rllib.algorithms.impala.impala import ImpalaConfig, LEARNER_RESULTS_CURR_ENTROPY_COEFF_KEY
  from ray.rllib.core.learner.learner import Learner
  from ray.rllib.utils.annotations import override
  from ray.rllib.utils.lambda_defaultdict import LambdaDefaultDict
  from ray.rllib.utils.schedules.scheduler import Scheduler
  from ray.rllib.utils.typing import ModuleID
label_desc: Use image node_id 1 for calling the ImpalaLearner obj's underlying member method code with example usage: obj.build() without return types