I'm wondering how could I make a symbol (in math mode) that looks more or less like this:
I need to introduce some symbols for my thesis, to represent some sets of elements that are 'entry points' and 'exit points' of some clusters, and I've used already too many letters of mathcal and mathscr, so for the sake of clarity, I'd like to have some symbols that 'talk' to the readers.
I've tried to find an existing symbol using detexify without success.
So I think the next step is to somehow build it myself, and I have too little experience in it to manage to create them (I can have the arrow above or below the circle, I can't have it entering or exiting the circle)

