old_contents: # Copyright (c) Paul R. Tagliamonte <tag@pault.ag>, 2015
  #
  # Permission is hereby granted, free of charge, to any person obtaining a
  # copy of this software and associated documentation files (the "Software"),
  # to deal in the Software without restriction, including without limitation
  # the rights to use, copy, modify, merge, publish, distribute, sublicense,
  # and/or sell copies of the Software, and to permit persons to whom the
  # Software is furnished to do so, subject to the following conditions:
  #
  # The above copyright notice and this permission notice shall be included in
  # all copies or substantial portions of the Software.
  #
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  # DEALINGS IN THE SOFTWARE.
  
  import asyncio
  from .api import Synth
  
  
  class AsyncSynth(Synth):
  
      @asyncio.coroutine
      def chord(self, channel, keys, velocity, duration):
          """
          Play a chord (series of keys) and async sleep.
          """
          for key in keys:
              self.noteon(channel, key, velocity)
          yield from asyncio.sleep(duration)
          for key in keys:
              self.noteoff(channel, key)
  
new_contents: # Copyright (c) Paul R. Tagliamonte <tag@pault.ag>, 2015
  #
  # Permission is hereby granted, free of charge, to any person obtaining a
  # copy of this software and associated documentation files (the "Software"),
  # to deal in the Software without restriction, including without limitation
  # the rights to use, copy, modify, merge, publish, distribute, sublicense,
  # and/or sell copies of the Software, and to permit persons to whom the
  # Software is furnished to do so, subject to the following conditions:
  #
  # The above copyright notice and this permission notice shall be included in
  # all copies or substantial portions of the Software.
  #
  # THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  # IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  # FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  # THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  # LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  # FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  # DEALINGS IN THE SOFTWARE.
  
  import asyncio
  from .api import Synth
  
  
  class AsyncSynth(Synth):
  
      @asyncio.coroutine
      def chord(self, channel, keys, velocity, duration):
          """
          Play a chord (series of keys) and async sleep.
          """
          for key in keys:
              self.noteon(channel, key, velocity)
          yield from asyncio.sleep(duration)
          for key in keys:
              self.noteoff(channel, key)
  
      @asyncio.coroutine
      def note(self, channel, key, velocity, duration):
          self.noteon(channel, key, velocity)
          yield from asyncio.sleep(duration)
          self.noteoff(channel, key)
  
subject: add a note helper