I’m very new to Python. I want to write a code for the “Bulls and Cows” game, using recursion. I have some code, but it doesn’t work. Would be grateful for any hint!

import random
    
progNum=str(random.randint(1000,9999))
print("Guess the number. It contains 4 digits.")

userNum=list(input("Enter your number: "))

l1=progNum
l2=userNum


def check(bulls,cows):  
    
    if cows==4 and bulls==4:
        return ('right number')
    
    else:
        bulls=0
        cows=0
        if l1[0]==l2[0]:            
            cows=cows+1
            print('Cows{}'.format(cows))        
        if l2[0] in l1:
            bulls=bulls+1
            print('Bulls{}'.format(bulls))
        if l1[1]==l2[1]:
            cows=cows+1
            print('Cows{}'.format(cows))
        if l2[1] in l1:
            bulls=bulls+1
            print('Bulls{}'.format(bulls))
        if l1[2]==l2[2]:
            cows=cows+1
            print('Cows{}'.format(cows))
        if l2[2] in l1:
            bulls=bulls+1
            print('Bulls{}'.format(bulls))
        if l1[3]==l2[3]:
            cows=cows+1
            print('Cows{}'.format(cows))
        if l2[3] in l1:
            bulls=bulls+1
            print('Bulls{}'.format(bulls))
    check(bulls,cows)

     

I made a base condition for the game termination as
if cows==4 and bulls==4:return (‘right number’), but it seems that without without specifying the number of attempts, it continues until a number is guessed. I think if the base condition could be the number of attempts, like cows=cows+(x), where x the number of attempts.