Kivymd app

from kivy.app import App

from kivymd.theming import ThemeManager
from kivy.lang import Builder
from kivy.uix.screenmanager import Screen


class MainScreen(Screen):
    pass


class OtherScreen(Screen):
    pass


presentation = Builder.load_file("main.kv")


class MainApp(App):
    theme_cls = ThemeManager()
    title = "My Application"

    def build(self):
        return presentation


if __name__ == "__main__":
    MainApp().run()