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Python fails to pass a Queue when calling Process with multiprocessing.set_start_method set to "spawn" or "forkserver".
Traceback (most recent call last):
 File "<string>", line 1, in <module>
 File "/usr/lib/python3.5/multiprocessing/spawn.py", line 106, in spawn_main
 exitcode = _main(fd)
 File "/usr/lib/python3.5/multiprocessing/spawn.py", line 116, in _main
 self = pickle.load(from_parent)
 File "/usr/lib/python3.5/multiprocessing/synchronize.py", line 111, in __setstate__
 self._semlock = _multiprocessing.SemLock._rebuild(*state)
FileNotFoundError: [Errno 2] No such file or directory
Here is a minimized example:
```
#!/usr/bin/env python3
import multiprocessing
def check_child(q):
 print("Queue", q)
if __name__ == '__main__':
 multiprocessing.set_start_method('spawn')
 # multiprocessing.set_start_method('fork')
 # multiprocessing.set_start_method('forkserver')
 q = multiprocessing.Queue(-1)
 print("q", q)
 proc = multiprocessing.Process(target=check_child, args=(q,))
 proc.start()
```
Also, this fails when the Queue is implicitly passed to the child.
```
class Blerg():
 def __init__(self):
 self.q = multiprocessing.Queue(-1)
 def print_queue(self):
 print("Queue", self.q)
if __name__ == '__main__':
 multiprocessing.set_start_method('spawn')
 blerg = Blerg()
 blerg.print_queue()
 proc = multiprocessing.Process(target=blerg.print_queue)
 proc.start()
```
$ python3 --version
Python 3.5.2
Windows (which defaults to "spawn" style multiprocessing) does not seem to have this issue (at least in 2.7.12).