:mod:`xml.dom.minidom` now validates namespaces in
:meth:`~xml.dom.Document.createElementNS`,
:meth:`~xml.dom.Document.createAttributeNS` and
:meth:`~xml.dom.Element.setAttributeNS`, and when setting
:attr:`~xml.dom.Node.prefix` of an attribute.
:exc:`~xml.dom.NamespaceErr` is now raised for a malformed qualified name, for
a prefix with an empty namespace, and for illegal use of the xml and
xmlns prefixes.