What is this part?

I am replacing my front driver's side fender on a 2006 Prius. I am wondering about some item that may have broken off, looks like it has wires coming from it and I do have one loose plug in that location...wonder if its essential or at least what it is so I can buy and replace. The item is not on my car body, but I do do have a plug with two wires in that location that are attached to nothing You can see the item in two of P-Cars photos on replacing the fender, img_0724 and img_0719. See: https://priuschat.com/attachments/img_0719-jpg.23198/
Thanks for any help.