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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _switchTo(self, newProto, clientFactory=None):
 """ Switch this Juice instance to a new protocol. You need to do this 'simultaneously' on both ends of a connection; the easiest way to do this is to use a subclass of ProtocolSwitchCommand. """


        assert self.innerProtocol is None, "Protocol can only be safely switched once."
        self.setRawMode()
        self.innerProtocol = newProto
        self.innerProtocolClientFactory = clientFactory
        newProto.makeConnection(self.transport)