Is a with on open always necessary?

[Roy Smith]

In article <mailman.4883.1327074990.27778.python-list at python.org>,
 Arnaud Delobelle <arnodel at gmail.com> wrote:

> > So maybe doing a
> >
> > with open(filename) as f:
> > Â  Â  contents = f.readlines()
> 
> That's what I do, unless I'm in an interactive session.

>From the resource management point of view, there's no doubt that's the 
right thing to be doing.  That being said, I don't bother most of the 
time and I can't think of a time when I've been bitten by it.