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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def to_graphviz(self) -> str: """ Converts the FSM behaviour structure to Graphviz syntax Returns: str: the graph in Graphviz syntax """

        graph = "digraph finite_state_machine { rankdir=LR; node [fixedsize=true];"
        for origin, dest in self._transitions.items():
            origin = origin.replace(" ", "_")
            for d in dest:
                d = d.replace(" ", "_")
                graph += "{0} -> {1};".format(origin, d)
        graph += "}"
        return graph