Update-alternatives

update-alternatives command provided by dpkg package.

• sudo update-alternatives --config editor
• sudo update-alternatives --config vi
• sudo update-alternatives --install /usr/bin/python python /usr/bin/python3 10

sudo update-alternatives --config editor
 Selection    Path                Priority   Status
------------------------------------------------------------
* 0            /bin/nano            40        auto mode
  1            /bin/ed             -100       manual mode
  2            /bin/nano            40        manual mode
  3            /usr/bin/vim.basic   30        manual mode
  4            /usr/bin/vim.tiny    15        manual mode

sudo update-alternatives --install /usr/bin/python python /usr/bin/python3 10
update-alternatives: using /usr/bin/python3 to provide /usr/bin/python (python) in auto mode

See also

• Editors: vi, vim, sed, awk, emacs, lineinfile (Ansible), Atom, paste, Neovim, Rider, visudo, vipw, update-alternatives, nano, more, less, .vimrc, set (vi) zed
• dpkg, dpkg-query, update-alternatives, ar, debsums, dpkg -V, dpkg -S, dpkg -L, dpkg --configure -a, wajig, dpkg -i -E , dpkg --help, dpkg-source-gitarchive

https://linux.die.net/man/8/update-alternatives