code: def test_others_empty():
      """Return None if no `others`."""
      assert (expand_grid(), None)
  
imports: from functools import reduce
  import numpy
  import pandas
  import pytest
  from hypothesis import given, settings
  from pandas.testing import assert_frame_equal
  import janitor
  from janitor.functions.expand_grid import expand_grid
  from janitor.testing_utils.strategies import categoricaldf_strategy, df_strategy
label_desc: Use image node_id 3 for calling a global function with example usage: test_others_empty() without return types