To make it easier I’d convert with some tools mp3 to wav, either:
$ ffmpeg -i foo.mp3 -vn -acodec pcm_s16le -ac 1 -ar 44100 -f wav foo.wav
or
$ mpg123 -w foo.wav foo.mp3
Then read the WAV with one of the python WAV libraries. I’d recommend PySoundFile because it works with most generated WAV correctly and installed without issue (as opposed to scikits.audiolab).
Note: Even though scipy.io.wavfile.read() gave me a “WavFileWarning: Unfamiliar format bytes” warning, it also loaded the file properly.