Update with association using Sequelize.js - node.js

Question

I am trying to update with association using sequelize.js.
I have tried give example on stackoverflow namely the following links:
Sequelize update with association
Sequelize update with association
Updating attributes in associated models using Sequelize
all of these links did not get me to the goal i am trying to accomplish.
My model is as follow, I have a country module and a city module. a country has many cities. please refer to the module bellow.
Please advise.
country.js file
module.exports = function (sequelize, DataTypes) {
var country= sequelize.define('COUNTRY', {
COUNTRY_ID: {
type: DataTypes.INTEGER,
primaryKey: true,
autoIncrement: true
},
COUNTRY_NAME: DataTypes.STRING,
COUNTRY_CURRENCY: DataTypes.STRING
}, {
freezeTableName: true,
classMethods: {
associate: function (models) {
COUNTRY_ID.hasMany(models.CITIES, {
foreignKey: 'COUNTRY_ID'
})
}
},
instanceMethods: {
updateAssociation: function (onSuccess, onError) {
country.findAll({
where: {
COUNTRY_ID: req.params.country_id
},
include: [
{
model: sequelize.import('./cities.js'),
}
]
})
})
.then(country =>{
const updatePromises = country.map(countries =>{
return countries.updateAttributes(req.body);
});
const updatePromisescities = list.CITY.map(cities =>{
return cities.updateAttributes(req.body.CITYs[0]);
});
return sequelize.Promise.all([updatePromises, updatePromisescities ])
}).then(onSuccess).error(onError);
}
}
});
return country;
};
city.js file
module.exports = function (sequelize, DataTypes) {
var CITY = sequelize.define('LIST_CODE', {
CITY_ID: {
type: DataTypes.INTEGER,
primaryKey: true
},
COUNTRY_ID: {
type: DataTypes.INTEGER,
primaryKey: true
}
}, {
freezeTableName: true,
timestamps: false,
classMethods: {
associate: function (models) {
// associations can be defined here
CITY.belongsTo(models.COUNTRY, {
foreignKey: 'COUNTRY_ID'
})
}
}
});
return CITY;
};