Does a regex match of the mount entry string

def match_entry_line(str_to_match, regex_obj=MAIN_REGEX_OBJ):
    """Does a regex match of the mount entry string"""
    match_obj = regex_obj.match(str_to_match)
    if not match_obj:
        error_message = ('Line "%s" is unrecognized by overlay4u. '
                'This is only meant for use with Ubuntu Linux.')
        raise UnrecognizedMountEntry(error_message % str_to_match)
    return match_obj.groupdict()