code: def main(_):
      run(trajectories_per_actor=500, num_actors=2, unroll_len=20)
  
imports: import functools
  import queue
  import threading
  from typing import Any, Callable, NamedTuple
  from absl import app
  from absl import logging
  from bsuite.environments import catch
  import dm_env
  import haiku
  import jax
  import jax.numpy
  import numpy
  import optax
  import rlax
label_desc: Use image node_id 4 for calling a global function with example usage: main(_) without return types