# build graph with objects that know how to search

class Graph:
    def __init__(self, label, extra=None):
        self.name = label                                # nodes=inst objects
        self.data = extra                                # graph=linked objs
        self.arcs = []
    def __repr__(self): 
        return self.name
    def search(self, goal):
        Graph.solns = []
        self.generate([self], goal)  
        Graph.solns.sort(lambda x,y: cmp(len(x), len(y)))
        return Graph.solns
    def generate(self, path, goal):
        if self == goal:                                 # class == tests addr
            Graph.solns.append(path)                     # or self.solns: same
        else:
            for arc in self.arcs:
                if arc not in path:
                    arc.generate(path + [arc], goal)

if __name__ == '__main__': 
    import gtestobj1
    gtestobj1.tests(Graph)