def METHOD_NAME(self):
    self._assets_which_have_id = []
    _visited_nodes = []
    for node in self.xmltree.xpath(".//*[@id]"):
        if node.tag == "sub-article":
            continue
        i = 0
        for child_node in self._asset_nodes(node):
            if child_node not in _visited_nodes:
                self._assets_which_have_id.append(
                    Asset(
                        node=child_node,
                        parent_map=self._parent_map,
                        parent_node_with_id=node,
                        number=i,
                    )
                )
                _visited_nodes.append(child_node)
                i += 1