Что я делаю не так?

Question

[onlooked]

#:kivy 1.9.0

<PongGame> :     
    canvas : 
        Rectangle : 
            pos :  self . center_x  -  5 ,  0 
            size :  10 ,  self . height 
            
    Label : 
        font_size :  70   
        center_x :  root . width  /  4 
        top :  root . top  -  50 
        text :  "0" 
        
    Label : 
        font_size :  70   
        center_x :  root . width  *  3  /  4 
        top :  root . top  -  50 
        text :  "0"

При выполнении программы терминал пишет :

[INFO   ] [Logger      ] Record log in /home/sergey/.kivy/logs/kivy_16-01-14_2.txt
[INFO   ] [Kivy        ] v1.9.0
[INFO   ] [Python      ] v3.4.3 (default, Oct 14 2015, 20:28:29) 
[GCC 4.8.4]
[INFO   ] [Factory     ] 173 symbols loaded
[INFO   ] [Image       ] Providers: img_tex, img_dds, img_gif, img_sdl2, img_pil (img_ffpyplayer ignored)
 Traceback (most recent call last):
   File "main.py", line 16, in <module>
     PongApp () . run ()
   File "/usr/lib/python3/dist-packages/kivy/app.py", line 797, in run
     self.load_kv(filename=self.kv_file)
   File "/usr/lib/python3/dist-packages/kivy/app.py", line 594, in load_kv
     root = Builder.load_file(rfilename)
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1749, in load_file
     return self.load_string(data, **kwargs)
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1796, in load_string
     parser = Parser(content=string, filename=fn)
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1185, in __init__
     self.parse(content)
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1287, in parse
     objects, remaining_lines = self.parse_level(0, lines)
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1369, in parse_level
     current_object = ParserRule(self, ln, x[0], rlevel)
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1043, in __init__
     self._detect_selectors()
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1085, in _detect_selectors
     self._build_rule()
   File "/usr/lib/python3/dist-packages/kivy/lang.py", line 1101, in _build_rule
     'Invalid rule (must be inside <>)')
 kivy.lang.ParserException: Parser: File "./pong.kv", line 3:
 ...
       1:#:kivy 1.9.0
       2:
 >>    3:<PongGame> :     
       4:    canvas : 
       5:        Rectangle : 
 ...
 Invalid rule (must be inside <>)

В чем проблема?

Comments

[sim3x]

?PongApp () . run ()

[Roman K]

Ты очень любишь пробелы, да?

[onlooked]

Нет, это с офф сайта пример

Answer 1

[Максим Бич]

Пробелы перед двоеточиями уберите и будет вам счастье. На одни примеры полагаться нельзя, они у них не всегда рабочие.

Answer 2

[onlooked]

табуляция...