def convert_compartment_format_to_list(compartments):
    """Converts compartment to a list.

    Parameters
    ----------
    compartments : list of str or str
        Cell Painting compartment(s).

    Returns
    -------
    compartments : list of str
        List of Cell Painting compartments.
    """

    if isinstance(compartments, list):
        compartments = [x.lower() for x in compartments]
    elif isinstance(compartments, str):
        compartments = [compartments.lower()]

    return compartments