code: def test_clean_column_values():
      """Clean column values"""
      raw = pd.DataFrame({"raw": ["Abçdê fgí j"]})
      outcome = raw.clean_names(axis=None, column_names="raw").squeeze()
      assert outcome == "abcde_fgi_j"
  
file_path: pyjanitor/tests/functions/test_clean_names.py
imports: import pandas
  import pytest
  from janitor.errors import JanitorError
label_desc: Use image node_id 16 for calling a global function with example usage: test_clean_column_values() without return types