async def _detect_proxy(self):
        '''Return True if it appears we can connect to a SOCKS proxy,
        otherwise False.
        '''
        if self.protocol is SOCKS4a:
            remote_address = NetAddress('www.apple.com', 80)
        else:
            remote_address = NetAddress('8.8.8.8', 53)

        sock = await self._connect_one(remote_address)
        if isinstance(sock, socket.socket):
            sock.close()
            return True

        # SOCKSFailure indicates something failed, but that we are likely talking to a
        # proxy
        return isinstance(sock, SOCKSFailure)
Return True if it appears we can connect to a SOCKS proxy,
        otherwise False.