Replace the content of a node. NOTE: @content is supposed
          to be a piece of XML CDATA, so it allows entity references,
          but XML special chars need to be escaped first by using
           xmlEncodeEntitiesReentrant() resp. xmlEncodeSpecialChars().

def setContentLen(self, content, len):
        """Replace the content of a node. NOTE: @content is supposed
          to be a piece of XML CDATA, so it allows entity references,
          but XML special chars need to be escaped first by using
           xmlEncodeEntitiesReentrant() resp. xmlEncodeSpecialChars(). """
        libxml2mod.xmlNodeSetContentLen(self._o, content, len)