python graph class

class Graph:
    cycles=[]
    visited = []
    spanningTree = {}
    edges = {}

    def getCycle(self, node, ancestor):
        path = []
        while (node != ancestor):
            if node is None:
                return []
            path.append(node)
            node = self.spanningTree[node]
        path.append(node)
        return path

    def dfs(self, node):
        self.visited.append(node)
        for each in self.edges[node]:
            if each not in self.visited:
                self.spanningTree[each] = node
                self.dfs(each)
            else:
                cycle = self.getCycle(node, each)
                if len(cycle) > 2:
                    self.cycles.append(cycle)

    def getCycles(self):
        for each in self.edges:
            if each not in self.visited:
                self.spanningTree[each] = None
                self.dfs(each)

g = Graph()
g.edges = {1:[2,4], 2:[1,3,5], 3:[2,4,6], 4:[1,3,7], 5:[2,6], 6:[3,5,7], 7:[4,6]}

g.getCycles()

print g.cycles
#[[4, 3, 2, 1], [6, 7, 4, 3], [5, 6, 7, 4, 3, 2]]