code: def newChild(self, ns, name, content):
          
          if ns is None: ns__o = None
          else: ns__o = ns._o
          ret = libxml2mod.xmlNewChild(self._o, ns__o, name, content)
          if ret is None:raise treeError('xmlNewChild() failed')
          __tmp = xmlNode(_obj=ret)
          return __tmp
docs: Creation of a new child element, added at the end of
            @parent children list. @ns and @content parameters are
            optional (None). If @ns is None, the newly created element
            inherits the namespace of @parent. If @content is non None,
            a child list containing the TEXTs and ENTITY_REFs node will
            be created. NOTE: @content is supposed to be a piece of XML
            CDATA, so it allows entity references. XML special chars
            must be escaped first by using
            xmlEncodeEntitiesReentrant(), or xmlNewTextChild() should
             be used.