def post_multipart(self, url, params, files):
        """
        Generates and issues a multipart request for data files

        :param url: a string, the url you are requesting
        :param params: a dict, a key-value of all the parameters
        :param files:  a dict, matching the form '{name: file descriptor}'

        :returns: a dict parsed from the JSON response
        """
        resp = requests.post(
            url,
            data=params,
            params=params,
            files=files,
            headers=self.headers,
            allow_redirects=False,
            auth=self.oauth
        )
        return self.json_parse(resp)