Remove any non-alphanumeric or non-~ leading characters

    Checks the beginning of any provided lists for non-alphanumeric or
    non-~ (tilde) leading characters and removes them if found.
    Operates on (and possibly alters) the passed list.

    :param list char_list: a list or lists of characters
    :return: None
    :rtype: None

def _check_leading(*char_lists):
    """Remove any non-alphanumeric or non-~ leading characters

    Checks the beginning of any provided lists for non-alphanumeric or
    non-~ (tilde) leading characters and removes them if found.
    Operates on (and possibly alters) the passed list.

    :param list char_list: a list or lists of characters
    :return: None
    :rtype: None
    """
    logger.debug('_check_leading(%s)', char_lists)
    for char_list in char_lists:
        while (len(char_list) != 0 and not char_list[0].isalnum() and
                not char_list[0] == '~'):
            char_list.pop(0)
        logger.debug('updated list: %s', char_list)