Python scipy.optimize.f_min_l_bfgs_b algorithm: how to have extra outputs?

Question

I am using L-BFGS-B optimizer from Scipy package. Here is the documentation.

My code has the following structure. obj_func is the objective function that is used to minimize "a". In order to do so, obj_func should only return "a".

Question: Is there a way to obtain "b" and "c" from obj_func?

Currently I am using function attribute. But I am not sure this is the preferred way.

def obj_func(x, *args)
    a, b, c = compute(x) # compute is where major computation happens
    # I want to access b and c from outside the function
    obj_func.result = [b,c] # use function attribute
    return a

result = optimize.fmin_l_bfgs_b(obj_func, x0, bounds=bounds, args=args)
b, c = obj_func.result