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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 _split_sequences_multitraj(dtrajs, lag):
 """ splits the discrete trajectories into conditional sequences by starting state Parameters dtrajs : list of int-iterables discrete trajectories nstates : int total number of discrete states lag : int lag time """

    n = number_of_states(dtrajs)
    res = []
    for i in range(n):
        res.append([])
    for dtraj in dtrajs:
        states, seqs = _split_sequences_singletraj(dtraj, n, lag)
        for i in range(len(states)):
            res[states[i]].append(seqs[i])
    return res