A newbie question about class

[Laura Creighton]

You can't write 

class doIt(value=something-mutable):

and get the behaviour you want.

Instead, the idiom is

class doIt(value=None):

and then test for None.

If you use == instead of is in your test then it will fail when it is
absolutely fine for what you get passed to redefine __cmp__ or __eq__.
And won't you look silly.

Laura Creighton