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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 closed_sets(C, mincount_connectivity=0):
 """ Computes the strongly connected closed sets of C """

    n = np.shape(C)[0]
    S = connected_sets(C, mincount_connectivity=mincount_connectivity, strong=True)
    closed = []
    for s in S:
        mask = np.zeros(n, dtype=bool)
        mask[s] = True
        if C[np.ix_(mask, ~mask)].sum() == 0:  # closed set, take it
            closed.append(s)
    return closed