не запускается игра Python Kivy

При запуске проекта выдает ошибку: Traceback (most recent call last): File "main.py", line 88, in PongApp().run() File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\app.py", line 949, in run self._run_prepare() File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\app.py", line 918, in _run_prepare self.load_kv(filename=self.kv_file) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\app.py", line 691, in load_kv root = Builder.load_file(rfilename) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\builder.py", line 306, in load_file return self.load_string(data, **kwargs) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\builder.py", line 373, in load_string parser = Parser(content=string, filename=fn) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\parser.py", line 402, in init self.parse(content) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\parser.py", line 511, in parse objects, remaining_lines = self.parse_level(0, lines) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\parser.py", line 593, in parse_level current_object = ParserRule(self, ln, name, rlevel) File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\parser.py", line 254, in init self._detect_selectors() File "C:\Users\sulta\AppData\Local\Programs\Python\Python36\lib\site-packages\kivy\lang\parser.py", line 303, in _detect_selectors 'Only one root object is allowed by .kv') kivy.lang.parser.ParserException: Parser: File "C:\Users\sulta\PycharmProjects\pythonProject\PyPong\pong.kv", line 126:

 124:        x: root.width - self.width
 125:        center_y: root.center_y

126:Public Pastes 127:Untitled 128:HTML | 18 min ago | 0.01 KB

Only one root object is allowed by .kv

файл main.py: https://pastebin.com/PcCZ9LmH файл pong.kv: https://pastebin.com/wjEc6nWq