如何将生成的声音写入文件？

Question

"use strict";

class User {
    constructor(first_name, last_name, username, password) {
        this.first_name = first_name;
        this.last_name = last_name;
        this.username = username;
        this.password = password;
    }

    getFirstName() {
        return this.first_name;
    }

    getLastName() {
        return this.last_name;
    }

    getUsername() {
        return this.username;
    }

    getPassword() {
        return this.Password;
    }    
}

module.exports = User;

这是我到目前为止所做的，但它不起作用..