I took this edX class a few years ago, and it moves really fast. I already knew a little python and I barely made it through, but it didn't matter since I wasn't doing it for credit. It's geared towards high IQ types that got into MIT (which certainly isn't me, either).

If you're not headed into a Computer Science major, you'll probably benefit from a more general approach to learning python.

I completed this course and the follow-up 6.00.2x. This is the best course on introductory python I have seen and got me going when I completed it last summer. It is a time-consuming course, but the problems they give are in depth, well-explained, and organized thoroughly. Some of the questions are HARD, but I think that is better than the opposite of everything being too simplified.

I'm not sure it took me 15 hours per week, but it is a lot of time. The videos alone are several hours each week if I recall correctly. In my view well worth the time, but be ready for some challenging problems.

Also, the course certificate probably isn't necessary. Its easier to put on a resume if you get the certificate, but it doesn't add to the course experience. But if you treat it like a charitable donation, the certificate is worthwhile.