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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 : (M, M) 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 References .. [1] P. Metzner, C. Schuette and E. Vanden-Eijnden. Transition Path Theory for Markov Jump Processes. Multiscale Model Simul 7: 1192-1219 (2009) """

    if issparse(F):
        return sparse.tpt.total_flux(F, A=A)
    elif isdense(F):
        return dense.tpt.total_flux(F, A=A)
    else:
        raise _type_not_supported