repair a strap mount that stripped and change the fuel pump?

dropped the empty fuel tank to get it away from the vehicle to repair a strap mount that stripped and change the fuel pump. tilted the tank to check if all the fuel was out and heard something banging around inside. if I'm correct it's the fuel vent valve that connects to the 1/2-inch flex tubing from the filler tube. what you see is what i found plus a lightweight spring. Someone please tell me how it goes back together then i'll take care of it before installing the new fuel pump. i know it snaps into place but not how the three pieces fit together. i think it may have dislodged when moving the pump around and disconnecting the 1/2-inch flex vent tubing. see photos. what is this and where does it go?