libxml-sax-writer-perl 0.57-1.1 (amd64 binary) in ubuntu hirsute

 XML::SAX::Writer helps to serialize SAX2 representations of XML documents to
 strings, files, and other flat representations. It handles charset encodings,
 XML escaping conventions, and so forth. It is still considered alpha,
 although it has been put to limited use in settings such as XML::LibXML and
 the AxKit XML Application Server.