It's possible to stop the parent with a CTRL+c, and so here is the trace of blocking function:

$ ./python y.py 
parent 26706: wait child
child 26707: wait 60 seconds
^CProcess PoolWorker-2:
Traceback (most recent call last):
  File "y.py", line 13, in <module>
Traceback (most recent call last):
  File "/home/haypo/prog/HG/cpython/Lib/multiprocessing/process.py", line 263, in _bootstrap
    print(result.get(timeout=120))
  File "/home/haypo/prog/HG/cpython/Lib/multiprocessing/pool.py", line 539, in get
    self.run()
  File "/home/haypo/prog/HG/cpython/Lib/multiprocessing/process.py", line 118, in run
    self._target(*self._args, **self._kwargs)
  File "/home/haypo/prog/HG/cpython/Lib/multiprocessing/pool.py", line 102, in worker
    self.wait(timeout)
  File "/home/haypo/prog/HG/cpython/Lib/multiprocessing/pool.py", line 534, in wait
    task = get()
  File "/home/haypo/prog/HG/cpython/Lib/multiprocessing/queues.py", line 378, in get
    return recv()
KeyboardInterrupt
    self._cond.wait(timeout)
  File "/home/haypo/prog/HG/cpython/Lib/threading.py", line 241, in wait
    gotit = waiter.acquire(True, timeout)
KeyboardInterrupt
[61207 refs]