How to add a fourth, unrelated to all others, circle to matplotlib-venn.venn3 diagram

Question

I'm using the awesome matplotlib_venn to plot Venn diagram derived from three binary conditions. Unfortunately, besides the 7 cases covered by the venn3 function, my case includes an all false ('000') group.

Is there any built in way to do so?

I've failed to find it myself, so any instructions to hijack this plot (or correlated hacks) to include it by myself in the output is very welcome.

Answer 1

matplotlib-venn is build on top of matplotlib so you can add a circle with the normal matplotlib commands.

fig, ax = plt.subplots()
venn3(subsets, ax=ax)
c = plt.Circle((x, y), radius) 
ax.add_patch(c)