def gen_keywords(*args: Union[ANSIColors, ANSIStyles], **kwargs: Union[ANSIColors, ANSIStyles]) -> tuple:
    '''generate single escape sequence mapping.'''
    fields: tuple = tuple()
    values: tuple = tuple()
    for tpl in args:
        fields += tpl._fields
        values += tpl
    for prefix, tpl in kwargs.items():
        fields += tuple(map(lambda x: '_'.join([prefix, x]), tpl._fields))
        values += tpl
    return namedtuple('ANSISequences', fields)(*values)