code: def df():
      return pd.DataFrame(
          {"a": [1, 2, 3, 4], "b": [5, 6, 7, 8], "c": [0, 0, 0, 0]}
      )
  
file_path: pyjanitor/tests/functions/test_update_where.py
imports: import pandas
  import pytest
  from pandas.testing import assert_frame_equal
  from janitor.functions import update_where
label_desc: Use image node_id 2 for calling a global function with example usage: df() and returns: pd