A canning jar can be adapted as illustrated. It is supported by a strip of galvanized metal around the middle and hangs horizontally. The circular cut is made in the lid, but not all the way around. The cut-out piece is bent to form a small perch at the entrance.
You must be careful to bend over or tape the edges of this piece of cut metal, because it does have a sharp edge. Instead of a metal dome lid, a piece of plastic from a jug or frozen-food container can be inserted in the screw top instead, but there will be no perch.