code: def test_flatdim(space: gym.spaces.Space, flatdim: Optional[int]):
      """Checks that the flattened dims of the space is equal to an expected value."""
      if space.is_np_flattenable:
          dim = utils.flatdim(space)
          assert dim == flatdim, f"Expected {dim} to equal {flatdim}"
      else:
          with pytest.raises(
              ValueError,
          ):
              utils.flatdim(space)
  
file_path: gym/tests/spaces/test_utils.py
imports: from itertools import zip_longest
  from typing import Optional
  import numpy
  import pytest
  import gym
  from gym.spaces import Box, Graph, utils
  from gym.utils.env_checker import data_equivalence
  from tests.spaces.utils import TESTING_SPACES, TESTING_SPACES_IDS
label_desc: Use image node_id 1 for calling a global function with example usage: test_flatdim(space, flatdim) without return types