code: def get_tempo(artist, title):
      "gets the tempo for a song"
      results = song.search(artist=artist, title=title, results=1, buckets=['audio_summary'])
      if len(results) > 0:
          return results[0].audio_summary['tempo']
      else:
          return Nonf get_tempo(artist, title):
      "gets the tempo for a song"
      results = song.search(artist=artist, title=title, results=1, buckets=['audio_summary'])
      if len(results) > 0:
          return results[0].audio_summary['tempo']
      else:
          return None
docs: gets the tempo for a song