I want to write a simple function that inserts a timestamp at point for a date one week after the previous timestamp. I'm sure it's very simple. But I can't figure out how to do it.

i have this:

(defun mwp/one-week-later ()
  "add a new timestamp a week later than the previous one"

  (interactive)
  (save-excursion
    (let ((curpos (point)))
      (re-search-backward "<[0-9]\\{4\\}-[0-9]\\{2\\}-[0-9]\\{2\\}"  )
      (let* ((previous-ts (org-element-context)))
        (goto-char curpos)

        (INSERT COPY OF PREVIOUS-TS) ;; obviously this is fake. But what to replace it with?

        (org-timestamp-change 7 'dat)     )))

    )

What's the real solution? Thank you,

Matt