Python NameError，变量“未定义”

您需要在函数main之外定义变量“生存”，然后在要引用该全局变量的任何函数中定义“生存”。当您在函数中并将值分配给变量时，它将假定它在本地范围内。使用“全球生命”告诉该函数将全球范围视为生命的参考。

import randomimport timelives = 10win = Falseguess = 0rand_num = 45def main():    global guess, rand_num, lives, win    win = False    rand_num = 45    lives = 10    while lives > 0 and win == False:        guess = int(input("Guess a number!"))        compare()    print("Well done!")    time.sleep(3)def compare():    global guess, rand_num, lives, win    if guess == rand_num:        print("You guessed correct!")        win = True    elif guess > rand_num:        print ("Guess lower!")        lives = lives - 1    else:        print ("Guess higher!")        lives = lives - 1def repeat():    replay = input("would you like to play again? Y/N")    if replay == "Y":        print("enjoy!")        main()    elif replay == "N":        "Goodbye then, hope you enjoyed!"        time.sleep(3)        os._exit    else:        print("please enter Y or N")        repeat()main()repeat()