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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 make_csr(A):
 """ Convert A to CSR, if A is not a CSR or BSR matrix already. Parameters A : array, matrix, sparse matrix (n x n) matrix to convert to CSR Returns ------- A : csr_matrix, bsr_matrix If A is csr_matrix or bsr_matrix, then do nothing and return A. Else, convert A to CSR if possible and return. Examples -------- Implicit conversion of A to CSR in pyamg.blackbox.make_csr """

    # Convert to CSR or BSR if necessary
    if not (isspmatrix_csr(A) or isspmatrix_bsr(A)):
        try:
            A = csr_matrix(A)
            print('Implicit conversion of A to CSR in pyamg.blackbox.make_csr')
        except BaseException:
            raise TypeError('Argument A must have type csr_matrix or\
                    bsr_matrix, or be convertible to csr_matrix')

    if A.shape[0] != A.shape[1]:
        raise TypeError('Argument A must be a square')

    A = A.asfptype()

    return A