title: python SOMETIMES os.environ has no pythonpath
body: <p>if i run the following script in Aptana Studio 3:</p>
  
  <pre><code>import os
  from pprint import pprint
  pprint(os.environ['PYTHONPATH'].split(os.pathsep))
  </code></pre>
  
  <p>I get the following output:</p>
  
  <pre><code>['C:\\Users\\Phocas_Tommy\\plugins\\org.python.pydev_3.0.0.1388187472\\pysrc\\pydev_sitecustomize',
   'D:\\Phocas\\Phocas-Automation',
   'D:\\Phocas\\Phocas-Automation\\analytics',
   'C:\\Users\\Phocas_Tommy\\plugins\\org.python.pydev_2.7.0.2013032300\\pysrc',
   'C:\\Windows\\system32\\python27.zip',
   'C:\\Python27\\DLLs',
   'C:\\Python27\\lib',
   'C:\\Python27\\lib\\plat-win',
   'C:\\Python27\\lib\\lib-tk',
   'C:\\Python27',
   'C:\\Python27\\lib\\site-packages']
  </code></pre>
  
  <p>If i run the same script in sublime text 3 i get the this error:</p>
  
  <pre><code>Traceback (most recent call last):
    File "D:\Phocas\Phocas-Automation\scrapbook.py", line 3, in &lt;module&gt;
      pprint(os.environ['PYTHONPATH'].split(os.pathsep))
    File "C:\Python27\lib\os.py", line 423, in __getitem__
      return self.data[key.upper()]
  KeyError: 'PYTHONPATH'
  </code></pre>
  
  <p>Totally confused - Could it be something to do with a project file being read by Aptana, telling the interpreter where to look for the PYTHONPATH? I don't understand why os.environ['PYTHONPATH'] is completely absent when i run it in sublime.</p>
  
  <p>I'm using python 2.7 on Windows Server 2008 R2 Standard</p>