How do I delay a line of code in tkinter without it crashing?

Question

So I ran into a problem in which when I used time.sleep() in tkinter, it crashed. I would like to know how I could delay code in tkinter without it crashing.

code related to the problem:

def count():
    global secs_left
    secs_left_label = Label(window, text=f'Secs left: {secs_left}', font=('Comic Sans', 50), bg='white')
    secs_left_label.place(relx=0.5, rely=0.35, anchor=CENTER)
    while True:
        if secs_left <= 0:
            break
        secs_left -= 1
        secs_left_label['text'] = f'Secs left: {secs_left}'