Python Decorator- (what ,types and why)

What?

• Decoration is a  way to specify management code for functions and classes
• Decorator themselves take the form of callable objects (ie., function ) that process other callable objects 

Types?

• Decorator are mainly two type
• function Decorator
• class Decorator

• function Decorator install wrapper object to intercept later function calls and process them as needed
• class Decorator install wrapper objects to intercept later instance creation calls and process them as required

Why?

• Decorators have very explicit syntax which makes them easier to spot than helper function class that may be arbitrarily far removed from the subject functions or classes.
• Decorators are applied once, when the subject function or class is defined; its not necessary to add extra code at every call to the class or function