def _on_reply_headers(self):
        reply = self.sender()
        request = reply.request()
        self._handle_reply_cookies(reply)
        self._run_webpage_callbacks(request, "on_response_headers", reply)

        har = self._get_har()
        if har is not None:
            har.store_reply_headers_received(self._get_request_id(request), reply)

        self.log("Headers received for {url}", reply, min_level=3)
Signal emitted before reading response body, after getting headers
dataset/ETHPy150Open scrapinghub/splash/splash/network_manager.py/ProxiedQNetworkAccessManager._on_reply_headers