That's generally considered unpythonic though. A more pythonic way to write that is for child in node.children if node.children else []: for attrib

That's generally considered unpythonic though. A more pythonic way to write that is for child in node.children if node.children else []: for attrib in child.attributes if child.attributes else []: ... Which, granted, is a lot more verbose and probably not any more readable but at least it's not abusing the or operator.