classStatePrefixEqOracle(Oracle):"""    Equivalence oracle that achieves guided exploration by starting random walks from each state a walk_per_state    times. Starting the random walk ensures that all states are reached at least walk_per_state times and that their    surrounding is randomly explored. Note that each state serves as a root of random exploration of maximum length    rand_walk_len exactly walk_per_state times during learning. Therefore excessive testing of initial states is    avoided.    """def__init__(self,alphabet:list,sul:SUL,walks_per_state=10,walk_len=12,depth_first=False):"""        Args:            alphabet: input alphabet            sul: system under learning            walks_per_state:individual walks per state of the automaton over the whole learning process            walk_len:length of random walk            depth_first:first explore newest states        """

ifself.depth_first:# reverse sort the states by length of their access sequences# first do the random walk on the state with longest access sequencestates_to_cover.sort(key=lambdax:len(x.prefix),reverse=True)else:random.shuffle(states_to_cover)