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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 _coord(self):
 """Attribute indicating the tree coordinates for this node. The tree coordinates of a node are expressed as a tuple of the indices of the node and its ancestors, for example: A grandchild node with node path `/root.name/root.childs[2].name/root.childs[2].childs[0].name` would have coordinates `(2,0)`. The root node _coord is an empty tuple: `()` :returns: the tree coordinates for this node. :rtype: tuple """

        _coord = []
        _node = self
        while _node.parent:
            _idx = _node.parent.childs.index(_node)
            _coord.insert(0, _idx)
            _node = _node.parent
        return tuple(_coord)