$wgParser->startExternalParse( $title, new ParserOptions(), Parser::OT_HTML );
$frame = $wgParser->getPreprocessor()->newFrame();
$ret = $wgParser->callParserFunction( $frame, '#tag',
$wgParser->startExternalParse( $title, new ParserOptions(), Parser::OT_HTML );
$frame = $wgParser->getPreprocessor()->newFrame();
$ret = $wgParser->callParserFunction( $frame, '#tag',