Add chatgpt-shell config

.gitmodules

@@ -0,0 +1,3 @@
+[submodule "chatgpt-shell"]
+	path = chatgpt-shell
+	url = https://github.com/xenodium/chatgpt-shell

config.org

@@ -1306,6 +1306,28 @@
           'clang-format-region-or-buffer)))
    #+end_src
 
+** ChatGPT
+   The =chatpt-shell= package is in a git submodule, so this has to be
+   added to the [[help:load-path][load-path]] and ~require~'d:
+
+   #+begin_src emacs-lisp
+     (let ((path (concat (getenv "HOME")
+                         "/.emacs.d/chatgpt-shell")))
+       (add-to-list 'load-path path))
+     (require 'chatgpt-shell)
+   #+end_src
+
+   [[help:chatgpt-shell-openai-key][chatgpt-shell-openai-key]] must also be set to a function that
+   returns an OpenAI API key. I have a key (made on [[https://platform.openai.com/account/api-keys][this page]]) stored
+   in =pass(1)= under =openai/api-key=, so this can be retrieved via
+   [[help:process-lines][process-lines]]:
+
+   #+begin_src emacs-lisp
+     (setq chatgpt-shell-openai-key
+           (lambda ()
+             (car (process-lines "pass" "openai/api-key"))))
+   #+end_src
+
 * Backup and Autosave
 ** Keep $PWD Tidy
    Emacs' default behaviour of dumping temporary files in the current