ipython zmq error

gistfile1.txt

{
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   "metadata": {
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   },
   "outputs": [
    {
     "data": {
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       "'0.70a1'"
      ]
     },
     "execution_count": 1,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import multiprocessing as mp\n",
    "mp.__version__"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
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   "outputs": [
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      ]
     },
     "execution_count": 2,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import IPython\n",
    "IPython.version_info"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": false
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       "(2, 2, 0)"
      ]
     },
     "execution_count": 3,
     "metadata": {},
     "output_type": "execute_result"
    }
   ],
   "source": [
    "import zmq\n",
    "zmq.zmq_version_info()"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "pool = mp.Pool(processes=4)"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": [
    "def cube(x): return x **3 "
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": false
   },
   "outputs": [],
   "source": [
    "pool.map(cube, range(8))"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": null,
   "metadata": {
    "collapsed": true
   },
   "outputs": [],
   "source": []
  }
 ],
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   "pygments_lexer": "ipython2",
   "version": "2.7.9"
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 },
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 "nbformat_minor": 0
}

gistfile2.txt

ZMQError                                  Traceback (most recent call last)
/usr/lib/python2.7/runpy.pyc in _run_module_as_main(mod_name='IPython.kernel.__main__', alter_argv=1)
    160         sys.argv[0] = fname
    161     return _run_code(code, main_globals, None,
--> 162                      "__main__", fname, loader, pkg_name)
        fname = '/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/__main__.py'
        loader = <pkgutil.ImpLoader instance at 0x7fa32c00cbd8>
        pkg_name = 'IPython.kernel'
    163 
    164 def run_module(mod_name, init_globals=None,

/usr/lib/python2.7/runpy.pyc in _run_code(code=<code object <module> at 0x7fa33216ceb0, file "/...ite-packages/IPython/kernel/__main__.py", line 1>, run_globals={'__builtins__': <module '__builtin__' (built-in)>, '__doc__': None, '__file__': '/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/__main__.py', '__loader__': <pkgutil.ImpLoader instance>, '__name__': '__main__', '__package__': 'IPython.kernel', 'app': <module 'IPython.kernel.zmq.kernelapp' from '/ho.../site-packages/IPython/kernel/zmq/kernelapp.pyc'>}, init_globals=None, mod_name='__main__', mod_fname='/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/__main__.py', mod_loader=<pkgutil.ImpLoader instance>, pkg_name='IPython.kernel')
     70                        __loader__ = mod_loader,
     71                        __package__ = pkg_name)
---> 72     exec code in run_globals
        code = <code object <module> at 0x7fa33216ceb0, file "/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/__main__.py", line 1>
        run_globals = {'__builtins__': <module '__builtin__' (built-in)>, '__file__': '/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/__main__.py', '__package__': 'IPython.kernel', '__name__': '__main__', 'app': <module 'IPython.kernel.zmq.kernelapp' from '/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/zmq/kernelapp.pyc'>, '__loader__': <pkgutil.ImpLoader instance at 0x7fa32c00cbd8>, '__doc__': None}
     73     return run_globals
     74 

/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/__main__.py in <module>()
      1 if __name__ == '__main__':
      2     from IPython.kernel.zmq import kernelapp as app
----> 3     app.launch_new_instance()
        global app.launch_new_instance = <bound method MetaHasTraits.launch_instance of <class 'IPython.kernel.zmq.kernelapp.IPKernelApp'>>

/home/kain88/.local/lib/python2.7/site-packages/IPython/config/application.pyc in launch_instance(cls=<class 'IPython.kernel.zmq.kernelapp.IPKernelApp'>, argv=None, **kwargs={})
    571         """
    572         app = cls.instance(**kwargs)
--> 573         app.initialize(argv)
        app.initialize = <bound method IPKernelApp.initialize of <IPython.kernel.zmq.kernelapp.IPKernelApp object at 0x7fa32bf5df10>>
        argv = None
    574         app.start()
    575 

/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/zmq/kernelapp.pyc in initialize(self=<IPython.kernel.zmq.kernelapp.IPKernelApp object>, argv=None)

/home/kain88/.local/lib/python2.7/site-packages/IPython/config/application.pyc in catch_config_error(method=<function initialize>, app=<IPython.kernel.zmq.kernelapp.IPKernelApp object>, *args=(None,), **kwargs={})
     73     """
     74     try:
---> 75         return method(app, *args, **kwargs)
        method = <function initialize at 0x7fa32bf67668>
        app = <IPython.kernel.zmq.kernelapp.IPKernelApp object at 0x7fa32bf5df10>
        args = (None,)
        kwargs = {}
     76     except (TraitError, ArgumentError) as e:
     77         app.print_help()

/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/zmq/kernelapp.pyc in initialize(self=<IPython.kernel.zmq.kernelapp.IPKernelApp object>, argv=None)
    346         self.init_connection_file()
    347         self.init_poller()
--> 348         self.init_sockets()
        self.init_sockets = <bound method IPKernelApp.init_sockets of <IPython.kernel.zmq.kernelapp.IPKernelApp object at 0x7fa32bf5df10>>
    349         self.init_heartbeat()
    350         # writing/displaying connection info must be *after* init_sockets/heartbeat

/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/zmq/kernelapp.pyc in init_sockets(self=<IPython.kernel.zmq.kernelapp.IPKernelApp object>)
    214         self.shell_socket = context.socket(zmq.ROUTER)
    215         self.shell_socket.linger = 1000
--> 216         self.shell_port = self._bind_socket(self.shell_socket, self.shell_port)
        self.shell_port = 40196
        self._bind_socket = <bound method IPKernelApp._bind_socket of <IPython.kernel.zmq.kernelapp.IPKernelApp object at 0x7fa32bf5df10>>
        self.shell_socket = <zmq.sugar.socket.Socket object at 0x7fa32bf4a328>
    217         self.log.debug("shell ROUTER Channel on port: %i" % self.shell_port)
    218 

/home/kain88/.local/lib/python2.7/site-packages/IPython/kernel/zmq/kernelapp.pyc in _bind_socket(self=<IPython.kernel.zmq.kernelapp.IPKernelApp object>, s=<zmq.sugar.socket.Socket object>, port=40196)
    158                 port = s.bind_to_random_port(iface)
    159             else:
--> 160                 s.bind("tcp://%s:%i" % (self.ip, port))
        s.bind = <built-in method bind of Socket object at 0x7fa32bf4a328>
        self.ip = u'127.0.0.1'
        port = 40196
    161         elif self.transport == 'ipc':
    162             if port <= 0:

zmq/backend/cython/socket.pyx in zmq.backend.cython.socket.Socket.bind (zmq/backend/cython/socket.c:4102)()

/home/kain88/.local/lib/python2.7/site-packages/zmq/backend/cython/checkrc.pxd in zmq.backend.cython.checkrc._check_rc (zmq/backend/cython/socket.c:6261)()
     19         else:
     20             from zmq.error import ZMQError
---> 21             raise ZMQError(errno)
        global ZMQError = <class 'zmq.error.ZMQError'>
        global errno = undefined
     22         # return -1
     23     return 0

ZMQError: Address already in use