recurse

test = {1:1, 2:{2.1:2.1}, 3:{3.1:{3.2:3.2}}}


def r(a, path=[]):
    for k,v in a.iteritems():
        if type(v) == dict:
            path.append(k)
            r(v, path)
            path.pop()
        else:
            print path, k, v


r(test)