how to return response to event the telnet-client nodejs

I need your help about how return the response to execute cmd on telnet-client, in this momment just have te response in the event 'ready' but don´t have return to principal funcion.

this is my code

const testTelnet = async (host, dns) => {

process.on('unhandledRejection', error => {
    console.log("**TELNET CONNECTION ERROR ***", error);

});

const params = {
    host: host,
    port: 23,
    shellPrompt: '#',
    negotiationMandatory: false,
    loginPrompt: dns + ' login:',
    username: user,
    password: password,
    failedLoginMatch: '/error en autenticacion/',
    timeout: 5000,
}

const res = connection.on('ready', prompt => {

    connection.exec(cmd, (err, response) => {
        console.log("pront", prompt);
        console.log(response)
        return response;  // **** NEED RETURN THIS RESPONSE
    })
})

console.log("resultado: ", res)

connection.on('timeout', () => {
    console.log('socket timeout!')
    connection.end()
})

connection.on('close', () => {
    console.log('connection closed')
})

connection.connect(params)

return response;

}