Why can I set properties during instantiation through __init__, but not through another method?

This is working

class a:
    def __init__(self,ka,sif):
        self.ka = ka
        self.sif = sif
    def b(self):
        pass

c = a("d","e")
c
print(c.ka,c.sif)

but

This is not working

class a:
    def __init__(self):
        pass
    def b(self,ka,sif):
        self.ka = ka
        self.sif = sif

c = a().b("d","e")
c
print(c.ka,c.sif)

Why?

I expected the get same result. Why these are not have same results.

>Solution :

a("d","e") will call __init__ and return the new instance of the class a. Regular methods do not have this behavior.

The b method does not return anything (so it implicitly returns None); if you want to be able to chain that method, add return self at the end.