"return" 关键字有什么作用？

Question

"return" 关键字有什么作用？想明白了还是不懂。

def calculate_slices(people, slices_per_person):
    return people * slices_per_person
import math
def calculate_pizzas(slices, slices_per_pie):
    return math.ceil(slices / slices_per_pie)
def calculate_slices_left(slices_per_pie, pizzas, slices):
    total_slices = slices_per_pie * pizzas
    return total_slices - slices
def main():
    people = int(input("How many people?: "))
    slices_per_person = float(input("How many slices per person?: "))
    slices = calculate_slices(people, slices_per_person)
    slices_per_pie = int(input("How many slices per pie?: "))
    pizzas = calculate_pizzas(slices, slices_per_pie)
    print("You need", pizzas, "to feed", people, "people")
    slices_left = calculate_slices_left(slices_per_pie, pizzas, slices)
    print("There will be", slices_left, 'leftover slices')
main()

Answer 1

一条return语句用于结束函数调用的执行，并将结果（return关键字后的表达式的值）“returns”传递给调用者. return 语句之后的语句不执行。如果 return 语句没有任何表达式，那么特殊值 None 是 returned.

Answer 2

Return "sends back" 从函数到函数调用者的结果。

考虑这两个相似但不同的功能

def f():
    a=4
    return a

def f2():
    a=4

print(f(),f2())

这产生：

 4, None

"return" 关键字有什么作用？

What does the "return" keyword do?

python

python-3.x

spyder