cache filename to read for this type/id.

        :param type_: str, "user" or "tag"
        :param id_: int, eg. 123456
        :returns: str

def filename(self, type_, id_):
        """
        cache filename to read for this type/id.

        :param type_: str, "user" or "tag"
        :param id_: int, eg. 123456
        :returns: str
        """
        profile = self.connection.profile
        return os.path.join(self.directory, profile, type_, str(id_))