def add_facts_stream(self, assessment, data_type, options, data):
        """
        To add  facts data stream to a Assessment
        :param datastream: string
        :param data_type: string
        :param options: dict
        :param data: Stream
        """

        url = self.get_fact_url(assessment,options)

        form_data = {
            'files': {
                'data': (
                    Utils.random_string(10)+('.json' if data_type == 'json' else '.csv'),
                    data,
                    'text/plain;charset=UTF-8',
                    {'Expires': '0'}
                )
            }
        }
        response = self.http.upstream(url,form_data)
        return response