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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 total_flux(F, A=None):
 r"""Compute the total flux, or turnover flux, that is produced by the flux sources and consumed by the flux sinks Parameters F : (n, n) ndarray Matrix of flux values between pairs of states. A : array_like (optional) List of integer state labels for set A (reactant) Returns ------- F : float The total flux, or turnover flux, that is produced by the flux sources and consumed by the flux sinks """

    if A is None:
        prod = flux_production(F)
        zeros = np.zeros(len(prod))
        outflux = np.sum(np.maximum(prod, zeros))
        return outflux
    else:
        X = set(np.arange(F.shape[0]))  # total state space
        A = set(A)
        notA = X.difference(A)
        outflux = (F[list(A), :])[:, list(notA)].sum()
        return outflux