creds = json.loads(response.data)

            query = {}
            query['Action'] = 'AssumeRoleWithClientGrants'
            query['Token'] = creds['access_token']
            query['DurationSeconds'] = creds['expires_in']
            query['Version'] = '2011-06-15'

            query_components = []
            for key in query:
                if query[key] is not None: