I would like to bind `M-S-up` to `C-u 7 S-up` to move a timestamp a week forward (and `down` for back). A modification of [this](https://emacs.stackexchange.com/a/21736/5345) answer resulted in a "Symbol is void" error in Emacs.

I tried modifying the `define-keys` command, but was not successful, as Emacs then stated that "-up" could not follow after "M-S".

How can I configure a keybinding in my `~/.emacs` file to execute `C-u 7 S-up`?

**Update**

I placed the following, modified from the answer linked above, in the scratch buffer and evaluated it:

```
(define-key my-map (kbd "C-u 7 S-up") (kbd "M-S-up"))

```

Emacs returned `Symbol's value as variable is void: my-map`.