Is this Captcha vulnerable?

Question

Python

I wrote my own Captcha for Python (don't judge strictly, google captcha is tired of choosing pictures)
I want to know how vulnerable it is.
Please test for the possibility of "hacking"
test captcha
Please indicate weaknesses: is it possible to recognize OCR?

Answer 1

Well, at least it doesn't work! It's easy to check, open two tabs, or two browser windows at the same time and try to enter captcha back and forth. The result will amaze you greatly, and now open three or four windows at the same time. Or is it implied that your site will only work in a single-window format? I can open 5-8 tabs per site.

Answer 2

The simplest neuron "in 10 minutes on the knee" will recognize this captcha with a 95% chance

Answer 3

Something meaningful is better: "One hundred and twenty-five plus three", "Move the red slider", "How to spell 'not' with verbs
" just intercept/analyze/substitute.
Note Aleksey Cheremisin also do not forget to take into account.