rhythmbox error mp3 plugin

OS:Ubuntu 12.01 LTS
Boot:Live-cd
Software in question:Rhythmbox music player
Action done:Tried to play mp3 files
Results in Error :
"Required plugin could not be found  Python (v2.7) requires to install plugins to play media files of the following type: MPEG-1 Layer 3 (MP3) decoder"

What do i do next ?