title: How to set application path in music21
body: <p>I'm using Ubuntu 14.04 64bit.
  I don't know what to set on path to application. 
  I have installed music21 in anaconda3, but I got output as follows:</p>
  
  <blockquote>
    <p>music21.converter.subConverters.SubConverterException: Cannot find a valid application path for format midi. Specify this in your Environment by calling environment.set(None, 'pathToApplication')</p>
  </blockquote>
  
  <p>What application should I choose? I've seen a lot of pages but no one tells me what to set.</p>