Zooplus Senior Python Engineer interview questions

The interview process was horrible, they are very slow in replying. Even though I have answered all their question in the interview, they decided not to provide any offer, without giving any feedback. What is that about? The interviewer asked questions from a list of standard questions, then he moved forward to ask me to implement a Fibonacci sequence using a generator. He then moved further to ask question based on the code and expanded it to be included in a FastAPI module. I have implemented all the solutions cleanly, as well as took care of edge cases and the possibility of using StreamingResponse to improve efficiency. Regardless, they gave no explanations for why they did not select me. Don't bother with them, they seem overly pretentious.