> Also, do you generally teach advanced concepts in an introductory CS class?
This is also what I struggled to understand with other comments. An introductory CS class's purpose to introduce, warmup and invite students (most often w/ no background) to the world of CS. This means low barrier of entry. (which Python is well suited for).
Yes, there are other languages that offer more features and more explicitly but the point of intro CS classes is to spark the curiosity with a great feedback loop, while eliminating obstacles to learn.