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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 _subtract_path_flux(net_flux, path):
 """ Internal function for modifying the net flux matrix by subtracting a path's flux from every edge in the path. """


    net_flux = copy.copy(net_flux)

    net_flux[path[:-1], path[1:]] -= net_flux[path[:-1], path[1:]].min()

    # The above *should* make the bottleneck have zero flux, but
    # numerically that may not be the case, so just set it to zero
    # to be sure.
    bottleneck_ind = net_flux[path[:-1], path[1:]].argmin()
    net_flux[path[bottleneck_ind], path[bottleneck_ind + 1]] = 0.0

    return net_flux