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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 cons(f, mindepth):
 """ Makes a list of lists of reads at each site """

    C = ClustFile(f)
    for data in C:
        names, seqs, nreps = zip(*data)
        total_nreps = sum(nreps)
        # Depth filter
        if total_nreps < mindepth:
            continue

        S = []
        for name, seq, nrep in data:
            # Append sequence * number of dereps
            S.append([seq, nrep])

        # Make list for each site in sequences
        res = stack(S)
        yield [x[:4] for x in res if sum(x[:4]) >= mindepth]