from kivy.uix.label import Label
from kivy.clock import Clock
import time


class IncrediblyCrudeClock(Label):
    def __init__(self, **kwargs):
        Clock.schedule_interval(self.update, 1)
        super().__init__(**kwargs)

    def update(self, *args):
        self.text = time.asctime()


if __name__ == "__main__":
    from kivy.app import App
    from kivy.lang import Builder

    kv="""
BoxLayout:
    orientation: 'vertical'
    Label:
        text: 'Clock Test'
    IncrediblyCrudeClock:
        font_size: '50sp'
"""

    class TimeApp(App):
        def build(self):
            return Builder.load_string(kv)

    TimeApp().run()