Then don't. The differences aren't that big that it would take you more than an hour or two to learn them. It's just that it takes time and effort to port older code.
Unfortunately, I think what this means is definitely up for debate. Python3, "happening" may be nothing more than a permanent split, not the obsolescence of 2.
In fact, that's what it looks more and more like everyday.
What IS happening, is that libraries are not, will not, and cannot drop 2.7 support. The opposite isn't true and may never be.
Some libraries will never drop 2.7. I can see why some projects like Django may drop 2.7 in a few years. Django releases tend to break backwards compatibility over time anyway. I don't care either way. My older projects can't be easily upgraded from Django version to version, and my newer Projects start out on Py3k.
Python 3 is happening, and that's the reality.