exec -> exec function

```
➜ sudo pip install tarantool

Downloading/unpacking tarantool
  Downloading tarantool-0.3.4.tar.gz
  Running setup.py egg_info for package tarantool
    Traceback (most recent call last):
      File "<string>", line 16, in <module>
      File "/private/tmp/pip_build_root/tarantool/setup.py", line 9
        exec line
                ^
    SyntaxError: invalid syntax
    Complete output from command python setup.py egg_info:
    Traceback (most recent call last):

  File "<string>", line 16, in <module>

  File "/private/tmp/pip_build_root/tarantool/setup.py", line 9

    exec line

            ^

SyntaxError: invalid syntax
```



```
➜ python --version
Python 3.3.0
```

```
➜ pip --version
pip 1.4.1 from /opt/local/Library/Frameworks/Python.framework/Versions/3.3/lib/python3.3/site-packages (python 3.3)
```


https://github.com/mailru/tarantool-python/blob/master/setup.py#L9
http://docs.python.org/3/library/functions.html#exec