Org-mode: timestamp + effort -> time range

问题

I liked the question and answer at emacs - org-mode: creation time range from effort estimate - Stack Overflow. It is regarding taking a scheduled item and effort estimate and producing a time range.

I wanted a slightly different result, but I can't see how to modify it (I imagine modifying to org-deadline would be easy). Instead of a Scheduled item, I wanted to act on simply a Timestamp.

In other words, (cutting, pasting and removing Scheduled: from the linked question),

* TODO Sample todo
  <2014-04-18 Fr 10:00>
  :PROPERTIES:
  :Effort:   1h
  :END:

would become

* TODO Sample todo
 <2014-04-18 Fr 10:00-11:00>
 :PROPERTIES:
 :Effort:   1h
 :END:

I considered org-time-stamp and org-add-planning-info, but with no success.

Assistance appreciated.

来源：https://stackoverflow.com/questions/23235094/org-mode-timestamp-effort-time-range