If you locked the keys to your 2002 Mercedes C240 in your gastank which locks if the car is locked will you be able to get your keys from the gastank if the car is unlocked by a locksmith?

If you locked the keys to your 2002 Mercedes C240 in your gastank which locks if the car is locked will you be able to get your keys from the gastank if the car is unlocked by a locksmith?
On to of the fridgerator where you left them stupid!