code: def note2snd(pitch, quarters):
    
    dur = quarters * quarter_dur
    if pitch is None:
      return zeros(dur)
    freq = str2freq(pitch) * Hz
    return synth(freq, dur)
docs: Creates an audio Stream object for a single note.
  
    Parameters
    ----------
    pitch :
      Pitch note like ``"A4"``, as a string, or ``None`` for a rest.
    quarters :
      Duration in quarters (see ``quarter_dur``).