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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 send(self, message) :
        "alternative to Connection.send_preallocated."
        if not isinstance(message, Message) :
            raise TypeError("message must be a Message")
        #end if
        assert not self._sent, "preallocated has already been sent"
        serial = ct.c_uint()
        dbus.dbus_connection_send_preallocated(self._parent._dbobj, self._dbobj, message._dbobj, ct.byref(serial))
        self._sent = True
        return \
            serial.value