Since the upgrade to 2.7, PyCharm appears to be getting confused with syntax checking. I keep getting lots of errors flagged (the red wavy thing) which are in fact not errors at all. Programs run just fine. The only way to get rid of them is to restart PyCharm after which they sometimes return. It's quite annoying. I did not have these issues with the previous release...
Env: OS X 10.8.2