Kivy-python: error al ejecutar Hello world

Después de instalar Kivy, intenté ejecutar una aplicación Hello World, pero recibí un error. Lo busqué en Google pero no puedo encontrar una respuesta satisfecha. Aquí está el error:

[INFO   ] Kivy v1.8.0
[INFO   ] [Logger      ] Record log in /home/duong/.kivy/logs/kivy_14-04-16_1.txt
[INFO   ] [Factory     ] 157 symbols loaded
[DEBUG  ] [Cache       ] register <kv.lang> with limit=None, timeout=Nones
[DEBUG  ] [Cache       ] register <kv.image> with limit=None, timeout=60s
[DEBUG  ] [Cache       ] register <kv.atlas> with limit=None, timeout=Nones
[INFO   ] [Image       ] Providers: img_tex, img_dds, img_pygame, img_pil, img_gif 
[DEBUG  ] [Cache       ] register <kv.texture> with limit=1000, timeout=60s
[DEBUG  ] [Cache       ] register <kv.shader> with limit=1000, timeout=3600s
[INFO   ] [Text        ] Provider: pygame
[DEBUG  ] [App         ] Loading kv <./my.kv>
[DEBUG  ] [App         ] kv <./my.kv> not found
[DEBUG  ] [Window      ] Ignored <egl_rpi> (import error)
[INFO   ] [Window      ] Provider: pygame(['window_egl_rpi'] ignored)
[WARNING] [WinPygame   ] Video: failed (multisamples=2)
[WARNING] [WinPygame   ] trying without antialiasing
[ERROR  ] [Window      ] Unable to use pygame
[ERROR  ] [Window      ] The module raised an important error: "Couldn't find matching   GLX visual"
 Exception kivy.core.CoreCriticalException: CoreCriticalException("Couldn't find matching GLX visual",) in 'kivy.properties.dpi2px' ignored
[DEBUG  ] [Window      ] Ignored <egl_rpi> (import error)
[INFO   ] [Window      ] Provider: pygame(['window_egl_rpi'] ignored)
[WARNING] [WinPygame   ] SDL wrapper failed to import!
[DEBUG  ] [Window      ] Ignored <sdl> (import error)
[DEBUG  ] [Window      ] Ignored <x11> (import error)
[CRITICAL] [Window      ] Unable to find any valuable Window provider at all!
[CRITICAL] [App         ] Unable to get a Window, abort.

Respuestas a la pregunta(2)

Su respuesta a la pregunta