def _extended_refactoring(filename, line):
    """
    Private function which does extra checkings
    when refactoring :epkg:`pyquickhelper`.

    @param      filename        filename
    @param      line            line
    @return                     None or error message
    """
    if "from pyquickhelper import fLOG" in line:
        if "test_code_style" not in filename:
            return "issue with fLOG"
    if "from pyquickhelper import noLOG" in line:
        if "test_code_style" not in filename:
            return "issue with noLOG"
    if "from pyquickhelper import run_cmd" in line:
        if "test_code_style" not in filename:
            return "issue with run_cmd"
    if "from pyquickhelper import get_temp_folder" in line:
        if "test_code_style" not in filename:
            return "issue with get_temp_folder"
    return None