OOPS Python Self и создание объекта класса и вызова функции

class A:
    def a(self,st):
        return 1
            
    def b(self,s1,s2) :
        d= self.a(7)
        return d    
obj=A()
print(obj.b(1,2))
//prints 1
// so basically every function in a class have self which is object
// like in each of them self is there -- def a(self,st): & def b(self,s1,s2):
// used to other functions of that class and 
//it's used to call other functions & while calling that other function
// we don't write self inside it
// d= self.a(7)
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