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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def set_cookie( # type: ignore self, key: str, value: AnyStr='', max_age: Optional[Union[int, timedelta]]=None, expires: Optional[datetime]=None, path: str='/', domain: Optional[str]=None, secure: bool=False, httponly: bool=False, ) -> None: """Set a cookie in the response headers. The arguments are the standard cookie morsels and this is a wrapper around the stdlib SimpleCookie code. """

        if isinstance(value, bytes):
            value = value.decode()  # type: ignore
        cookie = create_cookie(key, value, max_age, expires, path, domain, secure, httponly)  # type: ignore  # noqa: E501
        self.headers.add('Set-Cookie', cookie.output(header=''))