xlsx2csv 0.20+20161027+git5785081-1 (ppc64el binary) in ubuntu bionic

 xlsx files are zip archives where spreadsheet data is stored. In
 order to process a file, various bits inside the archive need to be
 located. This utility uses the Expat SAX parser to collect the strings
 into a simple dictionary, keyed by their relative position in the XML
 file. This makes it possible to process files of any size.