code: def test_others_none(df):
      """Return DataFrame if no `others`, and df exists."""
      assert_frame_equal(df.expand_grid("df"), df)
  
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 2 for calling a global function with example usage: test_others_none(df) without return types