People tend to say something along the lines of "The best way to learn is by doing" but I've always found that unless you're specifically learning a language to contribute to some project it's difficult to actually find little problems to tackle to keep yourself going.
A good solution to this is Project Euler, which has a list of various programming\mathematics challenges ranging from simple to quite brain-taxing. As an example, the first challenge is:
If we list all the natural numbers below 10 that are multiples of 3 or 5, we get 3, 5, 6 and 9. The sum of these multiples is 23.
And by problem #50 it's already getting a little tougher
Which prime, below one-million, can be written as the sum of the most consecutive primes
There are 208 in total, but I think some new ones get added here and there.
While I already knew python fairly well before starting Project Euler, I found that I learned some cool tricks purely through using the language so much. Good luck!
