Creation of a new text node with an extra content length
           parameter. The text node pertain to a given document.

def newDocTextLen(self, content, len):
        """Creation of a new text node with an extra content length
           parameter. The text node pertain to a given document. """
        ret = libxml2mod.xmlNewDocTextLen(self._o, content, len)
        if ret is None:raise treeError('xmlNewDocTextLen() failed')
        __tmp = xmlNode(_obj=ret)
        return __tmp