title: pathos multiprocessing cannot pickle
body: <p>I am having a similar issue to this <a href="https://stackoverflow.com/questions/32856206/pickling-issue-with-python-pathos#comment53610587_32856206">person</a>. I am unable to run a simple multiprocessing routine in the pathos module and receive a pickling error.  Below is the code and error.</p>
  
  <pre><code>from pathos.multiprocessing import ProcessingPool
  import dill
  class ProcClass(object):
      def __init__(self):
          pass
      def f(self,x):
          return x*x
  pc = ProcClass()
  pl = ProcessingPool(3)
  print pl.map(pc.f, range(10))
  </code></pre>
  
  <p>The returned error:</p>
  
  <pre><code>Exception in thread Thread-2:
  Traceback (most recent call last):
    File "/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/threading.py", line 551, in __bootstrap_inner
      self.run()
    File "/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/threading.py", line 504, in run
      self.__target(*self.__args, **self.__kwargs)
    File "/Library/Frameworks/EPD64.framework/Versions/7.3/lib/python2.7/multiprocessing/pool.py", line 320, in _handle_tasks
      put(task)
  PicklingError: Can't pickle &lt;type 'function'&gt;: attribute lookup __builtin__.function failed
  </code></pre>
  
  <p>I have installed:  pp, dill, pox and multiprocessing then installed pathos. The install works but always gives me this error:</p>
  
  <hr>
  
  <p>WARNING: One of the following dependencies is unresolved:
      pp(ft) >=1.6.4.5
      dill >=0.2.4
      pox >=0.2.2
      (multi)processing </p>
  
  <hr>
  
  <p>Based on a response from the author of pathos to a similar question, it looks like there is a problem with the install. I have removed and reinstalled several times, each time verifying the proper dependancies are installed. I'm running on MacOS and using python 2.7.
  Any help will be greatly appreciated!</p>