Check the property lock (property_lock)

def _should_send_property(self, key, value):
        """Check the property lock (property_lock)"""
        to_json = self.trait_metadata(key, 'to_json', self._trait_to_json)
        if key in self._property_lock:
            # model_state, buffer_paths, buffers
            split_value = _remove_buffers({ key: to_json(value, self)})
            split_lock = _remove_buffers({ key: self._property_lock[key]})
            # A roundtrip conversion through json in the comparison takes care of
            # idiosyncracies of how python data structures map to json, for example
            # tuples get converted to lists.
            if (jsonloads(jsondumps(split_value[0])) == split_lock[0]
                and split_value[1] == split_lock[1]
                and _buffer_list_equal(split_value[2], split_lock[2])):
                return False
        if self._holding_sync:
            self._states_to_send.add(key)
            return False
        else:
            return True