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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(self, A, F, N, b):
 """ Solve linear system ``Ax = b`` using numeric factorization ``N`` and symbolic factorization ``F``. Store the solution in ``b``. Parameters A Sparse matrix F Symbolic factorization N Numeric factorization b RHS of the equation Returns ------- None """

        if self.sparselib == 'umfpack':
            umfpack.solve(A, N, b)

        elif self.sparselib == 'klu':
            klu.solve(A, F, N, b)