def check_if_all_entries_are_none(list_values):
    """
    Checks if all entries in list are None

    Parameters
    ----------
    list_values : list
        List with different values

    Returns
    -------
    is_all_none : bool
        Boolean. True, if all values are None. False, if, at least, one
        value is not None
    """

    #  Initial value
    is_all_none = True

    for val in list_values:
        if val is not None:
            is_all_none = False
            break

    return is_all_none