Element.getAttributeNS

Element.getAttributeNS(
   uri as String?,
   localname as String
) as String

Get the value of the attribute of this element with the given localname and namespace URI, if any.

Parameters
uri	Namespace URI of the attribute.
localname	Local name of the attribute.

cts.doc("example.xml").getElementById("ex1").
  getAttributeNS("http://www.w3.org/XML/1998/namespace","lang");