title: delay a task until certain time
body: <p>What I want to do in a python script is sleep a number of seconds until the required time is reached.  IE: if runAt setting is 15:20 and current time is 10:20, how can I work out how many seconds to sleep?  I'm not sure how to convert 15:20 to a time and current date then deduct the actual time to get the seconds.</p>