Error propagating exceptions on-non subclassable types #269

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TypeError                                 Traceback (most recent call last)
<ipython-input-138-0fe3676d9e18> in <module>()
     31     for i in range(iterations):
     32         pool = Parallel(n_jobs=max_jobs, verbose=5)
---> 33         out = pool(delayed(nlopt_optimization)(job_id) for job_id in range(max_jobs))
     34         solutions.extend(out)
     35 

/home/federico/anaconda/lib/python2.7/site-packages/joblib/parallel.pyc in __call__(self, iterable)
    658                 # consumption.
    659                 self._iterating = False
--> 660             self.retrieve()
    661             # Make sure that we get a last message telling us we are done
    662             elapsed_time = time.time() - self._start_time

/home/federico/anaconda/lib/python2.7/site-packages/joblib/parallel.pyc in retrieve(self)
    540                             )
    541                         # Convert this to a JoblibException
--> 542                         exception_type = _mk_exception(exception.etype)[0]
    543                         raise exception_type(report)
    544                     raise exception

/home/federico/anaconda/lib/python2.7/site-packages/joblib/my_exceptions.pyc in _mk_exception(exception, name)
     67         this_exception = type(this_name, (exception, JoblibException),
     68                     dict(__repr__=JoblibException.__repr__,
---> 69                         __str__=JoblibException.__str__),
     70                     )
     71         _exception_mapping[this_name] = this_exception

TypeError: type 'nlopt.ForcedStop' is not an acceptable base type