Traceback (most recent call last):

 "/usr/local/lib/python3.7/site-packages/tornado/ioloop.py", line 743, in _run_callback
ret = callback()

 "/usr/local/lib/python3.7/site-packages/zmq/eventloop/zmqstream.py", line 542, in <lambda>
self.io_loop.add_callback(lambda : self._handle_events(self.socket, 0))

 "/usr/local/lib/python3.7/site-packages/zmq/eventloop/zmqstream.py", line 456, in _handle_events
self._handle_recv()

 "/usr/local/lib/python3.7/site-packages/zmq/eventloop/zmqstream.py", line 486, in _handle_recv
self._run_callback(callback, msg)

 "/usr/local/lib/python3.7/site-packages/zmq/eventloop/zmqstream.py", line 438, in _run_callback
callback(*args, **kwargs)

 "/usr/local/lib/python3.7/site-packages/jupyter_client/threaded.py", line 93, in _handle_recv
msg = self.session.deserialize(smsg)

 "/usr/local/lib/python3.7/site-packages/jupyter_client/session.py", line 941, in deserialize
raise ValueError("Duplicate Signature: %r" % signature)ValueError: Duplicate Signature: b'05eb300dd8235702569ad66caacb197d324e1f4e101b029746a34ec6236fd592'
Traceback (most recent call last):

 "test.py", line 11, in <module>
l_c(x)

 "/Users/oonokenta/dev/chainer/chainer/links/connection/linear.py", line 86, in __call__
return linear.linear(x, self.W, self.b)AttributeError: 'Linear' object has no attribute 'W'