class_docstr: Replay Buffers for loading existing data.
docstr: Loads a OutOfGraphReplayBuffer replay buffer.
code: def _load_buffer(self, suffix):
      """Loads a OutOfGraphReplayBuffer replay buffer."""
      try:
          # pytype: disable=attribute-error
          logging.info(
              "Starting to load from ckpt %d from %s",
              int(suffix),
              self._data_dir,
          )
  
          replay_buffer = circular_replay_buffer.OutOfGraphReplayBuffer(
              *self._args, **self._kwargs
          )
          replay_buffer.load(self._data_dir, suffix)
          # pylint: disable = protected-access
          replay_capacity = replay_buffer._replay_capacity
          end_index = (
              self._replay_transitions_start_index
              + replay_capacity
              + replay_buffer._stack_size
          )
          logging.info("Capacity: %d", replay_buffer._replay_capacity)
          logging.info(
              "Start index: %d", self._replay_transitions_start_index
          )
          logging.info("End index: %d", end_index)
          for name, array in replay_buffer._store.items():
              # This frees unused RAM if replay_capacity is smaller than 1M
              replay_buffer._store[name] = array[
                  self._replay_transitions_start_index : end_index
              ].copy()
              logging.info(
                  "%s: %s", name, replay_buffer._store[name].shape
              )
          logging.info(
              "Loaded replay buffer from ckpt %d from %s",
              int(suffix),
              self._data_dir,
          )
          # pylint: enable=protected-access
          # pytype: enable=attribute-error
          return replay_buffer
      except tf.errors.NotFoundError:
          return None
  
file_path: dopamine/dopamine/labs/offline_rl/fixed_replay.py
imports: from absl import logging
  from batch_rl.fixed_replay.replay_memory import fixed_replay_buffer
  from dopamine.replay_memory import circular_replay_buffer
  import gin
  import numpy
  import tensorflow
label_desc: Use image node_id 2 for calling the JaxFixedReplayBuffer obj's underlying member method code with example usage: obj._load_buffer(suffix) and returns: replay_buffer, None