Python - 試圖運行代碼時什麼都不會發生。我甚至沒有得到一個錯誤

我想用Python創建一個小型博彩應用程序，當我嘗試運行該程序時，什麼也沒有發生。我正在使用IDLE。這是我的代碼：Python - 試圖運行代碼時什麼都不會發生。我甚至沒有得到一個錯誤

def bet(): 
    #balance = 100 
    x = 0 
    with open("bal.txt", "r") as f: 
     for l in f: 
      bal = (sum([int(a) for a in l.split()])) 
      while bal > 0: 
       print ("Your balance is: " + str(balance) + " credits.") 
       while x == 0: 
        print ("Enter the amount you would like to bet:") 
        bet = int(input()) 
        if bet > bal: 
         x = 0 
        elif bet < 0: 
         x = 0 
        else: 
         x = 1 
       print ("Pick a number between 1 and 20") 
       num = int(input()) 

       convbal = bal - bet 
       print ("Your bet is now locked in...") 
       print (" ") 
       print (" ") 

       import random 
       rannum = random.randint(1, 20) 
       print ("Your guess was: " + str(num)) 
       print (" ") 
       print ("The random number was: " + str(rannum)) 

       if rannum == num: 
        print ("WINNER") 
        bal = bal + (bet * 2) 
       else: 
        print ("LOSER") 
        print ("") 
        print ("")

這是我的結果收到殼：