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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def _show_one(audio_file):
    "given an audio file, print out the artist, title and some audio attributes of the song"
    print 'File:        ', audio_file
    pytrack = track.track_from_filename(audio_file)
    print 'Artist:      ', pytrack.artist if hasattr(pytrack, 'artist') else 'Unknown'
    print 'Title:       ', pytrack.title if hasattr(pytrack, 'title') else 'Unknown'
    print 'Track ID:    ', pytrack.id
    print 'Tempo:       ', pytrack.tempo
    print 'Energy:       %1.3f %s' % (pytrack.energy, _bar(pytrack.energy))
    if not pytrack.valence:
        # Track hasn't had latest attributes computed. Force an upload.
        pytrack = track.track_from_filename(audio_file, force_upload=True)
    print 'Valence:      %1.3f %s' % (pytrack.valence, _bar(pytrack.valence)) 
    print 'Acousticness: %1.3f %s' % (pytrack.acousticness, _bar(pytrack.acousticness))
    print