code: def setUp(self, capacity, num_steps):
      self.capacity = capacity
      self.num_steps = num_steps
  
imports: import collections
  import copy
  import os
  import tempfile
  import unittest
  import numpy
  import pytest
  import torch
  from pfrl import replay_buffer, replay_buffers
label_desc: Use image node_id 1 for calling the TestReplayBuffer obj's underlying member method code with example usage: obj.setUp(capacity, num_steps) without return types