def http_post(self, url, body=None, fields={}, files={}, content_type=None,
                  headers={}, *args, **kwargs):
        """Perform an HTTP POST on the given URL."""
        headers = headers.copy()

        if body is None:
            if fields is not None:
                body, content_type = self._build_form_data(fields, files)
            else:
                body = ''

        if content_type:
            headers['Content-Type'] = content_type

        headers['Content-Length'] = len(body) % '%d'

        return self.http_request(url, body=body, headers=headers,
                                 method='POST', **kwargs)
dataset/ETHPy150Open reviewboard/reviewboard/reviewboard/hostingsvcs/service.py/HostingServiceClient.http_post/swapped operands of `%`