Unknown function or method for .find() in keystone nodejs

I am facing this problem that .find is showing an unknown function or method. for this view.query('products', keystone.list('product').model.find()); Then when I open the page product I get this error "Error thrown for request: /products ReferenceError: Unknown keystone list "product" " var keystone= require('keystone');

exports= module.exports=function (req,res) {

var view=new keystone.View(req,res);
var locals=res.locals;

//set locals
locals.section= 'store';

view.query('products', keystone.list('product').model.find());

// load product

view.render('products');

}

via Mohsin Younas