Dear list, 

I have a quick question about parsing a string containing attributes.
My string has the following form
(setq my-string ":caption the caption :label fig-1 :width 10cm :something this is an extra option")
I'm looking for a function which produces an alist or plist with the option value pair.
(:caption "the caption"
 :label "fig-1"
 :width "10cm
 :something "this is an extra option")

As org handels these string a lot when exporting, it seems to me 
that there must exist a build in function to solve this task.

Kind regards, 
Bob