Scary, but in a funny way.
If that happened to me, a Rat Snake in the bowl, I would probably followed this homeowner’s example, spend a few minutes soaping and rinsing the toilet bowl, then a few drops of Pine Sol or Febreeze with lemon scent. Only then, after I had gotten the bowl looking ‘presentable’ and aired the room out, would I call the police or health department.
Now, if I were somewhere in the tropics, and saw an angry Anaconda down there, flashing his fangs, all my vanity about presenting a clean rest room to the public would be put on hold. Too dangerous to matter at that point.
Anaconda don’t have fangs, they are constrictors...............