digraph state_automaton {
	{node [shape = circle] "state_b"};
	{node [shape = plaintext, style=invis, label=""] "__init_state_a"};
	{node [shape = doublecircle] "state_a"};
	{node [shape = circle] "state_a"};
	"__init_state_a" -> "state_a";
	"state_a" [label = "state_a"];
	"state_a" -> "state_a" [ label = "event_2" ];
	"state_a" -> "state_b" [ label = "event_1" ];
	"state_b" [label = "state_b"];
	"state_b" -> "state_a" [ label = "event_2" ];
	{ rank = min ;
		"__init_state_a";
		"state_a";
	}
}