khal can read and write events/icalendars to vdir, so vdirsyncer can 
be used to synchronize calendars with a variety of other programs,
for example CalDAV servers.

ikhal (interactive khal) lets you browse and edit calendars and events

No support for editing the timezones of events yet
Works with python 3.6+

To have completion with click, source the according file for your shell

in .bashrc
. /usr/doc/khal-*/khal-complete.bash

in .zshrc
. /usr/doc/khal-*/khal-complete.zsh

in .fishrc
. /usr/doc/khal-*/khal-complete.fish