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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 solve_sparse(self, B):
 """ Solve linear equation of the form A X = B. Where B and X are sparse matrices. Parameters B : any scipy.sparse matrix Right-hand side of the matrix equation. Note: it will be converted to csc_matrix via `.tocsc()`. Returns ------- X : csc_matrix Solution to the matrix equation as a csc_matrix """

        B = B.tocsc()
        cols = list()
        for j in xrange(B.shape[1]):
            col = self.solve(B[:,j])
            cols.append(csc_matrix(col))
        return hstack(cols)