def METHOD_NAME(self):
    recv = mitogen.core.Receiver(self.router)
    sender = recv.to_sender()
    sender2 = self.local.call(func_accepts_returns_sender, sender)
    self.assertEqual(sender.context.context_id,
                      sender2.context.context_id)
    self.assertEqual(sender.dst_handle, sender2.dst_handle)
    self.assertEqual(123, recv.get().unpickle())
    self.assertRaises(mitogen.core.ChannelError,
                      lambda: recv.get().unpickle())