python中的错误："cannot unpack non-iterable NoneType object"

Question

好吧，我刚刚学习了一种在python中输入数据的不同方法，并尝试了一个函数：

def userInput():
n1 = float(input("Enter first number:  "))
n2 = float(input("Enter second number:  "))
n3 = float(input("Enter third number:  "))
print(n1)
print(n2)
print(n3)
num1, num2, num3 = userInput()

当我只返回n1、n2和n3时，我似乎也没有遇到问题，但当我打印浮动时，我得到了以下输出：

Enter first number:  1
Enter second number:  2
Enter third number:  3
1.0
2.0
3.0
Traceback (most recent call last):
File "C:/Users/sahar/PycharmProjects/Learningpython/Learning python.py", line 9, in <module>
num1, num2, num3 = userInput()
TypeError: cannot unpack non-iterable NoneType object

这是一个简单的问题，我只是好奇哈哈。

Answer 1

def userInput():
n1 = float(input("Enter first number:  "))
n2 = float(input("Enter second number:  "))
n3 = float(input("Enter third number:  "))
print(n1)
print(n2)
print(n3)
return n1, n2, n3

num1, num2, num3 = userInput()