I had given a technical interview which was about an hour for Python developer. They asked me an algorithm question which returns a contents of a page. I did everything, but forgot to write return statement at the end. My interviewer pointed me I had one bug and asked me to find out. I checked everything and couldnt find out. She pointed me that I forgot to put return. Everything else was okay. On the next few days, I got rejected over an email. To this day, I dont even know why I was rejected.