A managers is a interface through which django models performs query on databases, by default django provides one manager called objects which we are frequently using while performing django queries
Sometimes the validation provided by the framework is not enough as per your requirements, so you want to write your custom rule and apply it on your model as per you need Yii provides flexibility to write your own custom validator and inject into model class.
A list is kind of data type in python which are array like structure. In python, list holds homogeneous as well as heterogenous data, which means you can add string as well as integers in same list.
A sitemap is a xml file which tells search engines about the pages available in your website which can be crawled. Django has inbuilt functionality for generating sitemap.xml file. It automates the creation of sitemaps based on your models.
Decorator is a design pattern which is used for modifying existing objects without changing it.
jpegoptim and optipng these are two tools for optimising and reducing image size in linux terminal. These tool are very useful when you are serving images on website. This will help you to reduce loadtime for static content in website.
In python Strings are immutable data types, that means we cannot modify an object after it is created, to modify strings we have to again create a string object during runtime.
A Docker is designed to make developers life easier. Container based design helps developers to build, run and deploy applications in easier way with no dependencies. Docker helps to manage application and its dependencies in easy manner.
Functions are group of statements to perform specific task. Functions are used for break down larger applications into different smaller components. Function have return statements which returns something after execution of code block.
In linux to create alias or shortcut of any command we use alias command. We will create alias for ls -ltr command.
Alias is used for creating shorter commands that is synonym for more complex and longer commands.