Refresh the content of the input buffer, the old data are
          considered consumed This routine handle the I18N
           transcoding to internal UTF-8

def read(self, len):
        """Refresh the content of the input buffer, the old data are
          considered consumed This routine handle the I18N
           transcoding to internal UTF-8 """
        ret = libxml2mod.xmlParserInputBufferRead(self._o, len)
        return ret