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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 _coo_to_sparse_series(A, dense_index=False):
 """ Convert a scipy.sparse.coo_matrix to a SparseSeries. Use the defaults given in the SparseSeries constructor. """

    s = Series(A.data, MultiIndex.from_arrays((A.row, A.col)))
    s = s.sort_index()
    s = s.to_sparse()  # TODO: specify kind?
    if dense_index:
        # is there a better constructor method to use here?
        i = range(A.shape[0])
        j = range(A.shape[1])
        ind = MultiIndex.from_product([i, j])
        s = s.reindex(ind)
    return s