如何从KivyMD文本字段中获取文本？

from kivymd.app import MDApp
from kivymd.uix.textfield import MDTextField

class MyApp(MDApp):
    def build(self):
        text_field = MDTextField()
        return text_field

class MyApp(MDApp):
    def build(self):
        text_field = MDTextField()
        return text_field

    def get_text(self, instance):
        text = instance.text
        print(text)

class MyApp(MDApp):
    def build(self):
        text_field = MDTextField()
        text_field.bind(on_text=self.get_text)
        return text_field

    def get_text(self, instance, value):
        text = value
        print(text)