code: def test_raises():
      search_space = Numerical(0, 1, label="a")
      with pytest.raises(ValueError):
          # TODO: improve message
          TuningTrajectoryGenerator(search_space)
  
file_path: nni/test/algo/nas/strategy/test_rl_impl.py
imports: from functools import partial
  import numpy
  import pytest
  from tianshou.data import ReplayBuffer, Batch
  from tianshou.policy import BasePolicy
  from nni.mutable import Categorical, Numerical, CategoricalMultiple, MutableDict, MutableList, ExpressionConstraint
  from nni.nas.strategy._rl_impl import TuningTrajectoryGenerator, default_policy_fn
label_desc: Use image node_id 5 for calling a global function with example usage: test_raises() without return types