Выравнивание текста в Label

from kivy.app import App
from kivy.uix.label import Label
 
 
class Label_left(Label):
    pass
 
 
label = Label_left()
label.text_size = label.size
label.halign = 'left'
label.text = 'Очень длинная надпись'
 
class testApp(App):
    def build(self):
        return label
 
if __name__ == '__main__':
    testApp().run()

class Example(App):
    def build(self):
        self.root = FloatLayout()
        self.label = Label(text="I'm aligned :)", size_hint=(1.0, 1.0), halign="left", valign="middle")
        self.label.bind(size=self.label.setter('text_size'))    
        self.root.add_widget(self.label)
        return self.root

from kivy.lang import Builder
from kivy.app import App
from kivy.uix.label import Label
from kivy.uix.boxlayout import BoxLayout
 
 
class Label_align(Label):
    def __init__(self, text, halign='left', valign='middle'):
        super(Label_align, self).__init__()
        self.text_size = self.size
        self.text = text
        self.valign = valign
        self.halign = halign
    pass
 
 
class Label_list:
    def __init__(self, num):
        self.elements = []
        for n in range(num):
            self.elements.append(Label_align('очень длинный текст{}'.format(n+1), 'right', 'top'))
 
 
with open('test.kv',encoding='utf8') as f:
    Builder.load_string(f.read())
 
label_list = Label_list(5)
b_lay = BoxLayout(orientation='vertical')
for element in label_list.elements:
    b_lay.add_widget(element)
 
 
class testApp(App):
    def build(self):
        return b_lay
 
if __name__ == '__main__':
    testApp().run()