为什么我会收到 NameError？

Question

Here's a part of the the code I'm trying to run:

def func1():
    a = True
    while a == True:
        try:
            guess = int(input("guess it: "))
            a = False
        except ValueError:
            print("Not a valid number.")

import random
number = random.randint(0, 50)
print("Im thinking of a number between 0 and 50,")

func1()

if guess == number:
    print("Perfect, you got it from the first try!")

I don't know why I get this: NameError: name 'guess' is not defined, even though I defined it in "func1"

Answer 1

You're getting the error because guess only exists in the scope of func1() . You need to return the value guess from func1() to use it.

Like so:

def func1():
    a = True
    while a == True:
        try:
            guess = int(input("guess it: "))
            a = False
        except ValueError:
            print("Not a valid number.")
    return guess # i'm returning the variable guess

import random
number = random.randint(0, 50)
print("Im thinking of a number between 0 and 50,")

guess = func1() # I'm assigning the value of guess to the global variable guess

if guess == number:
    print("Perfect, you got it from the first try!")