currying

def f(state_tax, city_tax, income):
    return (state_tax + city_tax) * income
    
def f1(state_tax=0.15):
    def f2(city_tax=0.1):
        def f3(income):
            return f(state_tax, city_tax, income)
        return f3
    return f2

print(f1()()(100) )
print(f1(0.2)(0.2)(100))