Install libetpan-doc by entering the following commands in the terminal:
sudo apt update sudo apt install libetpan-doc
Description:
mail handling library - API documentation
libEtPan! is a mail library. It may be used for low-level mail handling: network protocols (IMAP/NNTP/POP3/SMTP over TCP/IP with or without SSL), local storage (mbox/MH/maildir) and message/MIME parsing. . This package provides library API documentation and test sources.
Homepage: http://www.etpan.org/libetpan.html
Version: 1.8.0-1
Section: universe/doc