digraph {
concentrate=true;overlap=scale;"rat=Trochilus" [label="rat\nTrochilus",shape=box,style=filled,color=deepskyblue];"rat=Trochilus" -> "tool=Trochilus" [label="similar",dir="both"];"tool=Trochilus" [label="tool\nTrochilus",shape=box,style=filled,color=deepskyblue];}