code: def test_multidiscrete_length():
      space = MultiDiscrete(nvec=[3, 2, 4])
      assert len(space) == 3
  
      space = MultiDiscrete(nvec=[[2, 3], [3, 2]])
      with pytest.warns(
          UserWarning,
          match="Getting the length of a multi-dimensional MultiDiscrete space.",
      ):
          assert len(space) == 2
  
imports: import pytest
  from gym.spaces import Discrete, MultiDiscrete
  from gym.utils.env_checker import data_equivalence
label_desc: Use image node_id 3 for calling a global function with example usage: test_multidiscrete_length() without return types