:param async_req bool: execute request asynchronously
        :param file file:
        :param content_type string: file content type
        :param post_params object: post parameters
        :param _return_http_data_only: response data without head status code
                                       and headers
        :param _preload_content: if False, the urllib3.HTTPResponse object will
                                 be returned without reading/decoding response

        :param async_req bool: execute request asynchronously
        :param file file:
        :param _return_http_data_only: response data without head status code
                                       and headers
        :param _preload_content: if False, the urllib3.HTTPResponse object will
                                 be returned without reading/decoding response