Obtain CLOCK duration from LOGBOOK drawer using Org Element

[Shakthi Kannan <shakthimaan@gmail.com>]

Hi,

How can I obtain the clocked time for each CLOCK entry in the LOGBOOK
drawer using Org Element? Consider the following Org example:

=== Org sample ===

* DONE Task A
    CLOSED: [2017-03-20 Mon 12:21]
    :PROPERTIES:
    :ESTIMATED: 1.5
    :ACTUAL:
    :OWNER: foo
    :END:
    :LOGBOOK:
    CLOCK: [2017-03-20 Mon 11:45]--[2017-03-20 Mon 12:15] =>  0:30
    CLOCK: [2017-03-17 Fri 20:15]--[2017-03-17 Fri 21:45] =>  1:30
    CLOCK: [2017-03-17 Fri 12:05]--[2017-03-17 Fri 13:05] =>  1:00
    :END:

=== END ===

I would like to obtain "0:30", "1:30" and "1:00" from the LOGBOOK
CLOCK entries, sum them up and update the :ACTUAL: value in the the
PROPERTIES drawer. How can this be done?

Appreciate your inputs in this regard.

Thanks!

SK

-- 
Shakthi Kannan
http://www.shakthimaan.com