def request(self, method, uri, headers=None, bodyProducer=None):
        """
        Send a client request which declares supporting compressed content.

        @see: L{Agent.request}.
        """
        if headers is None:
            headers = Headers()
        else:
            headers = headers.copy()
        headers.addRawHeader(b'accept-encoding', self._supported)
        deferred = self._agent.request(method, uri, headers, bodyProducer)
        return deferred.addCallback(self._handleResponse)

        Send a client request which declares supporting compressed content.

        @see: L{Agent.request}.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/web/client.py