Pass a tag name by itself or a namespace URI and a tag name to
create a qualified name. Alternatively, pass an Element to
extract its tag name. None as first argument is ignored in
order to allow for generic 2-argument usage.
The text property holds the qualified name in
{namespace}tagname notation. The namespace and
localname properties hold the respective parts of the tag
name.
You can pass QName objects wherever a tag name is expected. Also,
setting Element text from a QName will resolve the namespace prefix
on assignment and set a qualified text value. This is helpful in XML
languages like SOAP or XML-Schema that use prefixed tag names in
their text content.