Can't use multiprocessing module in IPython

I am having issues with the multiprocessing module when using IPython. It works fine running in my console. Simple example:

from multiprocessing import Pool

def f(x):
    return x*x

if __name__ == '__main__':
    p = Pool(5)
    print(p.map(f, [1, 2, 3]))

Process SpawnPoolWorker-1:
Traceback (most recent call last):
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\process.py", line 258, in _bootstrap
    self.run()
Process SpawnPoolWorker-3:
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\process.py", line 93, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\pool.py", line 108, in worker
    task = get()
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\queues.py", line 337, in get
    return _ForkingPickler.loads(res)
AttributeError: Can't get attribute 'f' on <module '__main__' (built-in)>
Traceback (most recent call last):
Process SpawnPoolWorker-4:
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\process.py", line 258, in _bootstrap
    self.run()
Traceback (most recent call last):
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\process.py", line 258, in _bootstrap
    self.run()
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\process.py", line 93, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\pool.py", line 108, in worker
    task = get()
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\queues.py", line 337, in get
    return _ForkingPickler.loads(res)
AttributeError: Can't get attribute 'f' on <module '__main__' (built-in)>
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\process.py", line 93, in run
    self._target(*self._args, **self._kwargs)
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\pool.py", line 108, in worker
    task = get()
  File "C:\Users\kinga\Anaconda3\lib\multiprocessing\queues.py", line 337, in get
    return _ForkingPickler.loads(res)
AttributeError: Can't get attribute 'f' on <module '__main__' (built-in)>

[takluyver]

I think that’s a limitation of multiprocessing, especially on Windows. This is from the multiprocessing docs:

Functionality within this package requires that the __main__ module be importable by the children. This is covered in Programming guidelines however it is worth pointing out here. This means that some examples, such as the multiprocessing.pool.Pool examples will not work in the interactive interpreter.

https://docs.python.org/3/library/multiprocessing.html#using-a-pool-of-workers

[fxmarty]

This should be explicitly stated in the documentation or in tutorials examples.