问问题节点js继承findAll错误TypeError:无法读取未定义的属性(读取'findAll')

EN

// import 
const  Models  = require('../models/users');


exports.signup = (req, res, next) => {
    let username = req.body.username;
    let password = req.body.password;
    Models.Model.findAll({where :{ username : username}}).then(function(onSucces){
        return res.status(200).json({res : "je suis ici"})
    }).catch(function(onFail){
        return res.status(500).json({error: "server error"});
    })
   

};

'use strict';
const {
  Model
} = require('sequelize');
module.exports = (sequelize, DataTypes) => {
  class Users extends Model {
    /**
     * Helper method for defining associations.
     * This method is not a part of Sequelize lifecycle.
     * The `models/index` file will call this method automatically.
     */
    static associate(models) {
      // define association here
    }
  }
  Users.init({
    username: DataTypes.STRING,
    password: DataTypes.STRING,
    recovery: DataTypes.STRING
  }, {
    sequelize,
    modelName: 'Users',
  });
  return Users;
};

exports.Model = Model;