Python syntax error on run

I get the following error when running the script on my environment:

```
>git issues
  File "C:\Program Files (x86)\Git/libexec/git-core\git-issues", line 335
    print [key for key in self.shelf.iterkeys()]
                 ^
SyntaxError: invalid syntax
```

I'm running Python 3.4.0 on Windows 8.
