adding legend in a static plot using `abmplot()`

[yunhwankim2]

I think it would be great if a legend can be added to a static plot generated by abmplot() function.
It can be according to the marker style. For example, a legend can indicate that circles stand for predators and squares stand for prey.
I'm not sure whether this function is already implemented, but I cannot find in the documentation.
Many thanks in advance.