code: def test_replay_k(self):
      self.replay_buffer = HERReplayBuffer(
          env_spec=self.env.spec,
          capacity_in_transitions=10,
          replay_k=0,
          reward_fn=self.env.compute_reward,
      )
  
      with pytest.raises(ValueError):
          self.replay_buffer = HERReplayBuffer(
              env_spec=self.env.spec,
              capacity_in_transitions=10,
              replay_k=0.2,
              reward_fn=self.env.compute_reward,
          )
  
file_path: garage/tests/garage/replay_buffer/test_her_replay_buffer.py
imports: import pickle
  import numpy
  import pytest
  from garage.envs import GymEnv
  from garage.replay_buffer import HERReplayBuffer
  from tests.fixtures.envs.dummy import DummyDictEnv
label_desc: Use image node_id 2 for calling the TestHerReplayBuffer obj's underlying member method code with example usage: obj.test_replay_k() without return types