为什么Python中的语法错误无效？

Question

import math
# Program intro
def main():
# float print functions for n, A, r

n = float(input('How much time in years do you need to pay back the loan?'))
A = float(input("What is the amount of money you would like to borrow in whole dollars $?"))
r = float(input("What is your desired interest rate in a whole number?"
P = (r + A) / (n * A)

为什么P =（r + A）/（n * A）是一个SyntaxError：语法无效

Answer 1

r = float(input("What is your desired interest rate in a whole number?"
                                                                      ^
                                                      Missing 2 parenthesis

正确的行看起来像：

r = float(input("What is your desired interest rate in a whole number?"))