Why NOT only one class per file?

[Malcolm Dew-Jones]

Chris Lasher (chris.lasher at gmail.com) wrote:
: A friend of mine with a programming background in Java and Perl places
: each class in its own separate file in .

Java doesn't actually require one class per file, it requires one public 
class per file.  You can have any number of helper classes in the same 
file.

Perl doesn't require anything, and files and classes are almost entirely 
different things (except by useful convention).

I'm only just getting into python, so I have no opinions yet.