As of Python 3, decimal notations of octal values for permission modes
are no longer permitted and will result in a `SyntaxError` exception
(`invalid token`).

Using the proper octal notation which is also Python 2.7 compatible will
fix this issue.

--HG--
extra : rebase_source : 2e897c51f04ad0ee69071f84b98df224f3af72d3