def set_tunnel(self, host, port=None, headers=None):
        self._tunnel_host = host
        self._tunnel_port = port
        if headers:
            self._tunnel_headers = headers
        else:
            self._tunnel_headers.clear()
Sets up the host and the port for the HTTP CONNECT Tunnelling.
dataset/ETHPy150Open OpenCobolIDE/OpenCobolIDE/open_cobol_ide/extlibs/future/backports/http/client.py/HTTPConnection.set_tunnel