def get_foo():
    def f(self, i):
        print(self,i)
    return f

class A(object):

    def __init__(self, x):
        self.x = x

    def __str__(self):
       return str(self.x)

    def __repr__(self):
       return str(self.x)

    foo = get_foo();


a = A(5)
a.foo(4)