Python 如何使用KV语言将按钮与功能绑定

我正在try 使用KivyMD和Python制作一个基本的用户界面(我是初学者)，但我有一些投标方面的问题.如果你们中有人能帮我，我将不胜感激.这是我的IDE返回给我的错误:

文件"C:\USERS\kaua.silva\Desktop\app_ig\app.kv"，第67行，位于 ON_RELEASE:root.get_Text() ^^ 文件"kivy\weismproxy.pyx"，第32行，在kivy.nedproxy.WeakProxy.getattr中. AttributeError:"FloatLayout"对象没有属性""Get_Text""

main.py file:个

from kivymd.tools.hotreload.app import MDApp
from kivy.lang import Builder
from kivy.core.window import Window

class App(MDApp):
    def get_texts(self):
        user_text_field = self.root.ids.username
        user_text_field = user_text_field.text

        password_text_field = self.root.ids.passoword
        password_text_field = password_text_field.text

        quantity_text_field = self.root.ids.quantity
        quantity_text_field = quantity_text_field.text

        return user_text_field, password_text_field, quantity_text_field

    KV_FILES = ["app.kv"]
    DEBUG = True
    def build_app(self):
        Window.size = (320, 370)
        Window.resizable = 0
        return Builder.load_file("app.kv")

App().run()

app.kv file:个

FloatLayout: #:kivy !
    Image:
        source: "src/images/instagram_bg.jpg"
        allow_stretch: True
        keep_ratio: False
    MDLabel: 
        text: "Comment Bot"
        color: "#FFFFFF"
        font_size: "38sp"
        font_name: "font.ttf"
        pos_hint: {"center_x": 0.59, "center_y": 0.9}
    MDIcon:
        icon: "instagram"
        color: "#FFFFFF"
        font_size: "45sp"
        pos_hint: {"center_x": 0.85, "center_y": 0.90}
    MDTextField:
        id: username
        line_color_normal: "#ffffff"
        line_color_focus: "#ffffff"
        hint_text: "Nome de usuário ou e-mail"
        size_hint_x: .8
        pos_hint: {"center_x": 0.5, "center_y": 0.75}
        mode: "rectangle"
        hint_text_color_normal: "white"
        hint_text_color_focus: "white"
        text_color_focus: "#ffffff"
        text_color_normal: "#ffffff"
        font_size: "20sp"
    MDTextField:
        id: password
        line_color_normal: "#ffffff"
        line_color_focus: "#ffffff"
        text_color: "#ffffff"
        hint_text: "Senha"
        size_hint_x: .8
        pos_hint: {"center_x": 0.5, "center_y": 0.57}
        mode: "rectangle"
        hint_text_color_normal: "white"
        hint_text_color_focus: "white"
        text_color_focus: "#ffffff"
        text_color_normal: "#ffffff"
        font_size: "20sp"
    MDTextField:
        id: quantity
        color_mode: "primary"
        line_color_normal: "#ffffff"
        line_color_focus: "#ffffff"
        hint_text: "Quantidade de comentários"
        size_hint_x: .8
        pos_hint: {"center_x": 0.5, "center_y": 0.39}
        mode: "rectangle"
        hint_text_color_normal: "white"
        hint_text_color_focus: "white"
        text_color_focus: "#ffffff"
        text_color_normal: "#ffffff"
        font_size: "20sp"
    MDRaisedButton:
        text: "Iniciar"
        theme_text_color: "Custom"
        text_color: "#FFFFFF"
        font_style: "Button"
        md_bg_color: "#C8439C"
        size_hint: .5, .13
        pos_hint: {"center_x": .5, "center_y": .155}
        font_size: "16sp"
        on_release: root.get_texts()

我想用MDRaisedButton绑定函数GET_TEXTS(它只是一个简单的函数，我将用另一个函数替换它)，但vscode无法识别该函数.谢谢你的到来！