selenium给正在运行的火狐浏览器换代理ip

ip ='127.0.0.1:80' # ip格式"127.0.0.1:80"
            driver.get("about:config");
            # js代码
            setupScript = '''var prefs = Components.classes["@mozilla.org/preferences-service;1"].getService(Components.interfaces.nsIPrefBranch);
            prefs.setIntPref("network.proxy.type", 1);
            prefs.setCharPref("network.proxy.http", "%s");
            prefs.setIntPref("network.proxy.http_port", "%s");
            prefs.setCharPref("network.proxy.ssl", "%s");
            prefs.setIntPref("network.proxy.ssl_port", "%s");
            prefs.setCharPref("network.proxy.ftp", "$%s");
            prefs.setIntPref("network.proxy.ftp_port", "%s");
            ''' % (
            ip.split(':')[0], ip.split(':')[1], ip.split(':')[0], ip.split(':')[1], ip.split(':')[0], ip.split(':')[1])
            # 执行js
            driver.execute_script(setupScript);