Erase references to children without deleting them.

        These children might be used somewhere else, otherwise they will be taken care by ``Python``'s garbage collector.

def detach_children(self):
        """
        Erase references to children without deleting them.

        These children might be used somewhere else, otherwise they will be taken care by ``Python``'s garbage collector.
        """
        for node in self.get_child_nodes():
            node.set_parent(None)
        self._nodes = dict()