class_docstr: Manages state and performs updates for IMPALA learner.
docstr: Enqueue trajectory.
docstr_tok: ["Enqueue","trajectory","."]
code: def enqueue_traj(self, traj: util.Transition):
      """Enqueue trajectory."""
      self._host_q.put(traj)
  
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 4 for calling the Learner obj's underlying member method code with example usage: obj.enqueue_traj(traj) without return types