[python] What is the purpose of the word 'self'?

"self" keyword holds the reference of class and it is upto you if you want to use it or not but if you notice, whenever you create a new method in python, python automatically write self keyword for you. If you do some R&D, you will notice that if you create say two methods in a class and try to call one inside another, it does not recognize method unless you add self (reference of class).

class testA:
def __init__(self):
    print('ads')
def m1(self):
    print('method 1')
    self.m2()
def m2(self):
    print('method 2')

Below code throws unresolvable reference error.

class testA:
def __init__(self):
    print('ads')
def m1(self):
    print('method 1')
    m2()  #throws unresolvable reference error as class does not know if m2 exist in class scope
def m2(self):
    print('method 2')

Now let see below example

class testA:
def __init__(self):
    print('ads')
def m1(self):
    print('method 1')
def m2():
    print('method 2')

Now when you create object of class testA, you can call method m1() using class object like this as method m1() has included self keyword

obj = testA()
obj.m1()

But if you want to call method m2(), because is has no self reference so you can call m2() directly using class name like below

testA.m2()

But keep in practice to live with self keyword as there are other benefits too of it like creating global variable inside and so on.

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