如何获得按键的持续时间？

Question

我试图使用python来获取按键的持续时间，但我的代码仅在第一次工作，然后下一次按键显示自程序执行以来的总时间。

from pynput import keyboard
import time

def keydet(key):
    return False

def keypress():
    def callb(key):  # what to do on key-release
        ti1 = time.time() - t

        ti2 = str(ti1)  # converting float value to string
        ti3 = ti2[0:5] # cutting the seconds ( time ) , without it , it will print like 0.233446546


        print("The key", key, "Pressed For", ti3)

        kp = key
        print(kp)

        a = time.sleep(0.0001)
        return key  # stop detecting more key-releases


    def callb1(key):  # what to do on key-press

        return False  # stop detecting more key-presses


    with keyboard.Listener(on_press=callb1) as listener1:  # setting code for listening key-press
        listener1.join()

    t = 0
    t = time.time()



    with keyboard.Listener(on_release=callb) as listener:  # setting code for listening key-release
        listener.join()


#Keypress Detector
with keyboard.Listener(on_press=keydet) as listener:
    keypress()

我试过谷歌搜索但无法找到最适合我的解决方案。我在这个网站上也看到了一些问题，但对我来说没什么用。