calibre 4.99.4+dfsg+really4.10.0+py3-2 (arm64 binary) in ubuntu focal

 Calibre is a complete e-library solution. It includes library management,
 format conversion, news feeds to e-book conversion, e-book viewer and editor,
 and e-book reader sync features.
 .
 Calibre is primarily an e-book cataloging program. It manages your e-book
 collection for you. It is designed around the concept of the logical book,
 i.e. a single entry in the database that may correspond to e-books in several
 formats. It also supports conversion to and from a dozen different e-book
 formats.
 .
 Calibre supports almost every single e-Reader (e.g., Kindle, Kobo, Nook) and
 is compatible with more devices with every update. Calibre can transfer your
 e-books from one device to another in seconds, wirelessly or with a cable.
 It will send the best file format for your device converting it if
 needed, automatically.
 .
 Calibre can automatically fetch news from a number of websites/RSS feeds,
 format the news into a e-book and upload to a connected device.
 .
 Calibre has also a built-in e-book viewer that can display all the major e-book
 formats.