text: 	// ( modelName, Schema )
  	const model = mongoose.model('review', Review);
  	
  	const newReview = new mongoose.model('review', {
  		text    : 'very good',
  		value   : 10,
  		service : 'red'
  	});
  	
  	newReview.save(console.log);
  	
  	mongoose.model('review').findOne({
  		
  		text    : 'very good',
  		value   : 10
  		
  	}, (err, it) => {
  		if (err) {
  			// error control code
  			return;
  		}
  		console.log(util.inspect(it));
  	});