title: Undefined variable from import when using protocol buffers in PyDev
body: <p>I've got a PyDev project that uses protocol buffers. The protocol buffer files are located in a zip file generated by the protoc compiler. Everything works when I run the program, however PyDev reports "Undefined variable from import" for every enumeration constant. So for example:</p>
  
  <pre><code>import model_pb2
  
  value = model_pb2.Expression(type = model_pb2.Expression.PARAMETER)
  </code></pre>
  
  <p>It reports the enum constant "PARAMETER" as being an undefined variable. There are several dozen similar errors in my program, and I'd like to fix them "properly" (i.e. not simply suppressing the warning.)</p>