Bulls and Cows Python

import random
attempts = 0

while True:
    num = str(random.randrange(1000,10000))
    count = [num.count(i) for i in num if num.count(i)>1]
    if not count: break

while True:
    guess = input()
    bulls, cows = 0,0
    attempts += 1

    if [guess.count(j) for j in guess if guess.count(j)>1]:
        print("Duplicate number entered, please try again")
        continue

    for idx,dgt in enumerate(guess):

        if dgt == num[idx]:
            bulls+=1
            continue

        elif dgt in num:
            cows+=1
            continue

    if bulls==4: print(f"Number : {num}\nAttempts : {attempts}")
    else: print(f"{bulls}A {cows}B")