A quick ruby crash course
This is a different sort of answer than what you may be hoping for, but I'd really recommend that you deepen your knowledge of Python first. Learn to be pythonic, learn its OOP aspects. Learn its dynamic aspects. Become a Python Wizard. 

The reason for this advice, since you are fairly new at this, is that there is a danger that you will try to learn too many languages too soon and start to think of them syntactically only. There are a lot of "java programmers" for example, who only write C code. 

Let me give an analogy from another field. I used to be a very good photographer. I had one manual film camera with a light meter and three lenses. One was a zoom lens since I wanted to backpack with not too much equipment. At that point I could take really nice photos. Artistic. Later I got lots of cameras, lots of lenses, lots of other "stuff" and my ability to really take good photos went down, not up. Too many tools in your tool box is not a help, especially for a beginner. 

So, build skill first, then branch out. One big idea is called "creativity under constraint". How much can you do if you artificially restrict your tool set? It sounds dumb at first, but with fewer tools your brain becomes your best and most powerful tool. Suppose your language didn't have loops. What can you still do? Recursion of course, but in an OOP language there are other options. Suppose, instead, it didn't have any sort of selection statements (if/switch...). Can you still write any program? Some become very difficult to write, but attempting to do this increases your brain power. Big Idea here.