title: "ImportError: No module named exceptions" when running Celery
body: <p>I'm attempting to run a Django app that uses Celery and I'm receiving the following error:</p>
  
  <pre><code>    import djcelery
    File "/Library/Python/2.7/site-packages/djcelery/__init__.py", line 25, in &lt;module&gt;
      from celery import current_app as celery  # noqa
    File "/Library/Python/2.7/site-packages/celery/__compat__.py", line 135, in __getattr__
      module = __import__(self._object_origins[name], None, None, [name])
    File "/Library/Python/2.7/site-packages/celery/_state.py", line 18, in &lt;module&gt;
      from celery.utils.threads import LocalStack
    File "/Library/Python/2.7/site-packages/celery/utils/__init__.py", line 24, in &lt;module&gt;
      from celery.exceptions import CPendingDeprecationWarning, CDeprecationWarning
    File "/Library/Python/2.7/site-packages/celery/exceptions.py", line 15, in &lt;module&gt;
      from billiard.exceptions import ( # noqa
  ImportError: No module named exceptions
  </code></pre>
  
  <p>billiard is installed and the <code>exceptions</code> module does exist, and I'm able to import billiard.exceptions via Python's interactive prompt without issues. It seems that celery is failing to import billiard. Any ideas?</p>