code

def make_rational(num, den):
    def dispatch(m):
        if m == 0:
            return num
        elif m == 1:
            return den
        else:
            print('Invalid input')
    return dispatch

r1 = make_rational(1, 2)
r2 = make_rational(3, 4)
num = r1(0)
den = r1(1)