Sketch of using edit-indirect to edit docstrings in rst

edit-indirect-rst.el

(use-package edit-indirect)

(defun edit-indirect-rst-set-mode (_parent _beg _end)
  (rst-mode))

(setq edit-indirect-guess-mode-function #'edit-indirect-rst-set-mode)

(defun edit-indirect-rst-remove-spaces()
  (save-excursion
    (beginning-of-buffer)
    (while (search-forward-regexp "^    \\(.*?\\)" nil t)
      (replace-match "\\1" nil))))

(defun edit-indirect-rst-add-spaces()
  (save-excursion
    (beginning-of-buffer)
    (while (search-forward-regexp "^\\([^\n]\\)" nil t)
      (replace-match "    \\1" nil))
    (end-of-buffer)
    (insert "    ")))

(add-to-list 'edit-indirect-after-creation-hook #'edit-indirect-rst-remove-spaces)
(add-to-list 'edit-indirect-before-commit-hook #'edit-indirect-rst-add-spaces)

(defun edit-indirect-region-wrap-rst (s e o)
  (edit-indirect-region s e o))

(defun edit-indirect-rst ()
  (interactive)
  (let ((pt (point)))
    (progn
      (save-excursion
        (setq s (re-search-backward "\\(\"\"\"\\)" nil t)
              region-start (match-end 0))
        (goto-char pt)
        (setq e (re-search-forward "\\(\"\"\"\\)" nil t)
              region-end (match-beginning 0))
        (and s e (< s pt e))))
    (edit-indirect-region-wrap-rst region-start region-end t)))

(global-set-key (kbd "C-c e") 'edit-indirect-rst)