a clean way to define dictionary

[Jeremy Hylton]

On Wed, 2003-06-18 at 04:22, Alex Martelli wrote:
> > also, i don't think it's a good idea to use dict as a variable name since
> > dict is a python type.
> 
> Very good advice!  If you use dict as a local name, you shadow the
> buit-in name 'dict' and therefore cannot any more call it e.g. in
> order to generate a new dictionary, as above.

Agreed.  When things go wrong, it can be very difficult to understand. 
Say you use file as a local variable, but through later editing delete
the assignment.  Later, you call file.read(25) or dict.update(obj).  You
get:

Traceback (most recent call last):
  File "<stdin>", line 1, in ?
TypeError: descriptor 'read' requires a 'file' object but received a
'int'

It's not obvious that you've called the unbound method on the builtin
type.

Jeremy