old_contents: """
  Module that contains the command line app.
  
  Why does this file exist, and why not put this in __main__?
  
    You might be tempted to import things from __main__ later, but that will cause
    problems: the code will get executed twice:
  
    - When you run `python -mtwelve_tone` python will execute
      ``__main__.py`` as a script. That means there won't be any
      ``twelve_tone.__main__`` in ``sys.modules``.
    - When you import __main__ it will get executed again (as a module) because
      there's no ``twelve_tone.__main__`` in ``sys.modules``.
  
    Also see (1) from http://click.pocoo.org/5/setuptools/#setuptools-integration
  """
  import click
  
  from twelve_tone.composer import Composer
  
  
  @click.command()
  @click.option('--midi', '-m', help='MIDI output file')
  def main(midi):
      c = Composer()
      c.compose()
      click.echo(c.get_melody())
      if midi is not None:
        c.save_to_midi(filename=midi)
  
new_contents: """
  Module that contains the command line app.
  
  Why does this file exist, and why not put this in __main__?
  
    You might be tempted to import things from __main__ later, but that will cause
    problems: the code will get executed twice:
  
    - When you run `python -mtwelve_tone` python will execute
      ``__main__.py`` as a script. That means there won't be any
      ``twelve_tone.__main__`` in ``sys.modules``.
    - When you import __main__ it will get executed again (as a module) because
      there's no ``twelve_tone.__main__`` in ``sys.modules``.
  
    Also see (1) from http://click.pocoo.org/5/setuptools/#setuptools-integration
  """
  import click
  
  from twelve_tone.composer import Composer
  
  
  @click.command()
  @click.option('--midi', '-m', help='MIDI output file')
  def main(midi):
      c = Composer()
      c.compose()
      click.echo(c.get_melody())
      if midi is not None:
          c.save_to_midi(filename=midi)
  
subject: Fix indentation