Sets an outgoing cookie name/value with the given options.

        Newly-set cookies are not immediately visible via `get_cookie`;
        they are not present until the next request.

        expires may be a numeric timestamp as returned by `time.time`,
        a time tuple as returned by `time.gmtime`, or a
        `datetime.datetime` object.

        Additional keyword arguments are set on the cookies.Morsel
        directly.
        See https://docs.python.org/3/library/http.cookies.html#http.cookies.Morsel
        for available attributes.

def set_cookie(
        self,
        name: str,
        value: Union[str, bytes],
        domain: str = None,
        expires: Union[float, Tuple, datetime.datetime] = None,
        path: str = "/",
        expires_days: int = None,
        **kwargs: Any
    ) -> None:
        """Sets an outgoing cookie name/value with the given options.

        Newly-set cookies are not immediately visible via `get_cookie`;
        they are not present until the next request.

        expires may be a numeric timestamp as returned by `time.time`,
        a time tuple as returned by `time.gmtime`, or a
        `datetime.datetime` object.

        Additional keyword arguments are set on the cookies.Morsel
        directly.
        See https://docs.python.org/3/library/http.cookies.html#http.cookies.Morsel
        for available attributes.
        """
        # The cookie library only accepts type str, in both python 2 and 3
        name = escape.native_str(name)
        value = escape.native_str(value)
        if re.search(r"[\x00-\x20]", name + value):
            # Don't let us accidentally inject bad stuff
            raise ValueError("Invalid cookie %r: %r" % (name, value))
        if not hasattr(self, "_new_cookie"):
            self._new_cookie = http.cookies.SimpleCookie()
        if name in self._new_cookie:
            del self._new_cookie[name]
        self._new_cookie[name] = value
        morsel = self._new_cookie[name]
        if domain:
            morsel["domain"] = domain
        if expires_days is not None and not expires:
            expires = datetime.datetime.utcnow() + datetime.timedelta(days=expires_days)
        if expires:
            morsel["expires"] = httputil.format_timestamp(expires)
        if path:
            morsel["path"] = path
        for k, v in kwargs.items():
            if k == "max_age":
                k = "max-age"

            # skip falsy values for httponly and secure flags because
            # SimpleCookie sets them regardless
            if k in ["httponly", "secure"] and not v:
                continue

            morsel[k] = v