title: Python - fails importing package
body: <p>I have trouble importing package.
  My file structure is like this:</p>
  
  <pre><code>filelib/  
      __init__.py
      converters/ 
          __init__.py
          cmp2locus.py
      modelmaker/ 
          __init__.py
          command_file.py
  </code></pre>
  
  <p>In module <code>command_file.py</code> I have a class named <code>CommandFile</code> which i want to call in the <code>cmp2locus.py</code> module.</p>
  
  <p>I have tried the following in <code>cmp2locus.py</code> module:</p>
  
  <pre><code>import filelib.modelmaker.command_file
  import modelmaker.command_file
  from filelib.modelmaker.command_file import CommandFile
  </code></pre>
  
  <p>All these options return <code>ImportError: No modules named ...</code>
  Appreciate any hint on solving this. I do not understand why this import does not work.</p>