when should I explicitly close a file?

[Lawrence D'Oliveiro]

In message <mailman.2119.1271898215.23598.python-list at python.org>, Chris 
Rebert wrote:

> On Wed, Apr 21, 2010 at 5:53 PM, Lawrence D'Oliveiro wrote:
>
>> In message <4bc9aadb$1 at dnews.tpgi.com.au>, Lie Ryan wrote:
>>
>>> Since in python nothing is guaranteed about implicit file close ...
>>
>> It is guaranteed that objects with a reference count of zero will be
>> disposed.
> 
>> In my experiments, this happens immediately.
> 
> Experiment with an implementation other than CPython and prepare to be
> surprised.

Any implementation that doesn’t do reference-counting is brain-damaged.