如何访问kivy中的小部件？我需要通过按一个按钮来删除TextInput

import kivy
from kivy.app import App
from kivy.uix.button import Button
from kivy.uix.textinput import TextInput
from kivy.uix.boxlayout import BoxLayout

class MyLayout(BoxLayout):
    def __init__(self, **kwargs):
        super(MyLayout, self).__init__(**kwargs)
        
        self.orientation = 'vertical'
        
        self.text_input = TextInput()
        self.add_widget(self.text_input)
        
        self.button = Button(text='删除', on_press=self.delete_text_input)
        self.add_widget(self.button)
        
    def delete_text_input(self, instance):
        self.remove_widget(self.text_input)

class MyApp(App):
    def build(self):
        return MyLayout()

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