KivyMD. Python. Ошибка

 from kivy.lang import Builder 
from kivymd.app import MDApp 
 
KV = ''' 
MDScreen: 
    md_bg_color: self.theme_cls.backgroundColor 
    MDButton: 
        style: "elevated" 
        pos_hint: {"center_x": .5, "center_y": .5} 
''' 
 
 
class Example(MDApp): 
    def build(self): 
        self.theme_cls.theme_style = "Dark" 
        self.theme_cls.primary_palette = "Olive"  # "Purple", "Red" 
        return Builder.load_string(KV) 
 
 
Example().run() 

  Traceback (most recent call last): 
   File "main.py", line 2, in <module> 
     from kivymd.app import MDApp 
   File "/home/vladimir/.local/lib/python3.8/site-packages/kivymd/app.py", line 65, in <module> 
     from kivymd.theming import ThemeManager 
   File "/home/vladimir/.local/lib/python3.8/site-packages/kivymd/theming.py", line 49, in <module> 
     from materialyoucolor.utils.color_utils import argb_from_rgba_01 
   File "/home/vladimir/.local/lib/python3.8/site-packages/materialyoucolor/utils/color_utils.py", line 1, in <module> 
     from materialyoucolor.utils.math_utils import matrix_multiply, clamp_int 
   File "/home/vladimir/.local/lib/python3.8/site-packages/materialyoucolor/utils/math_utils.py", line 53, in <module> 
     def matrix_multiply(row: list[float], matrix: list[list[float]]) -> list[float]: 
 TypeError: 'type' object is not subscriptable