There are quite a few alternatives for gradually discovering the range of features covered by Python, but there is one project that is well known and very well done.
It is the Python Module of the Week site.
A fundamentally simple idea: every week, the focus is put on a particular module and examples are written to show how to use it. Indeed, a good demonstration is often worth more than a long speech, and gradually, at a pace of 52 modules per year, you end up with more than substantial content.
Definitely worth discovering. An excellent place to spend your time.