Decorators in python.py

#decorators take a function as input and enhances it and returns the function
# function within a function which adds some features to the function and returns it

def decor(num):
    def inner():
        print("enhanced")
        num()
    return inner

def num1():
    print("this is num1")

nan=decor(num1)#nan have the returned inner() func of the decor function
nan()# so we again have to call enhanced num1 through inner, and its instance is nan///ERROR

print()

@decor#this line replaces the above 2 lines now we can call it just by num2()
def num2():
    print("this is num2")

num2()

#some of the builtin decorators are @classmethod @staticmethod or @abstracmethod from abc
class student:

    school="walter"#class variable

    def __init__(self,roll,age):
        self.rol=roll
        self.ag=age

    def get_rol(self):
        return self.rol

    def get_ag(self):#getter
        return self.ag

    def set_rol(self):#setter
        self.rol=0

    def set_ag(self):
        self.ag=5

    #def __get__(self, instance, owner):
     #   self.ag=instance
      #  student=owner

    @classmethod# using decorator
    def sch(cls):
        return cls.school#class method

    def scho(student):#class method without decorator
        return student.school

    @staticmethod#decorator
    def info():#static method can access class variables
        print("learning OOP", student.school)