title: MIDIutil is not creating/writing files
body: <p>I'm trying to use midiutil to create a program that converts text into a midi file. I have thus far been able to do everything successfully, however midiutil does not appear to be functioning correctly. When I execute the code, it appears to complete fine, but no file is written. I've tried copying and pasting the default example from the documentation, and the same problem occurs. The code appears to run correctly, but no file is created. I have also tried manually creating the file first in hopes that it might edit the existing file, but that also doesn't work. For reference, here is the example code from the documentation that is NOT working correctly when I attempt to run it.</p>
  <pre><code>from midiutil import MIDIFile
  
  degrees  = [60, 62, 64, 65, 67, 69, 71, 72] # MIDI note number
  track    = 0
  channel  = 0
  time     = 0   # In beats
  duration = 1   # In beats
  tempo    = 60  # In BPM
  volume   = 100 # 0-127, as per the MIDI standard
  
  MyMIDI = MIDIFile(1) # One track, defaults to format 1 (tempo track
                   # automatically created)
  MyMIDI.addTempo(track,time, tempo)
  
  for pitch in degrees:
      MyMIDI.addNote(track, channel, pitch, time, duration, volume)
      time = time + 1
  
  with open(&quot;major-scale.mid&quot;, &quot;wb&quot;) as output_file:
      MyMIDI.writeFile(output_file)
  </code></pre>