如何将变量中的文本插入到我制作的kivy标签中？

from kivy.uix.label import Label

text_variable = "Hello, World!"

label_text = "My Label: {}".format(text_variable)

label = Label(text=label_text)

from kivy.uix.boxlayout import BoxLayout

layout = BoxLayout()
layout.add_widget(label)

from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.boxlayout import BoxLayout

class MyApp(App):
    def build(self):
        text_variable = "Hello, World!"
        label_text = "My Label: {}".format(text_variable)
        label = Label(text=label_text)
        
        layout = BoxLayout()
        layout.add_widget(label)
        
        return layout

if __name__ == '__main__':
    MyApp().run()