Filter by Valid Through

I would like to suppress jobs that have passed the date set in the field ‘valid through’. I could not see a short code to do this. Is there any way to do this easily or do I have to do some custom coding for this? In our list of volunteer opportunities for our non-profit, we only want to show opportunities that are currently open and not those that have expired. We could of course change the category of the listing but we would like this to happen automatically rather than someone in the office having to remember to go back and update the jobs from time-to-time.

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