pretty basic instantiation question

[sittner at lkb.ens.fr]

i'm very new to python, but i have a pretty basic question:
let's say i have a class, and i need to create a different number of
instances (changes every time - and i can't know the number in advance) in
a loop.
a function receives the number of instances that are needed, and creates
them like,
a=Myclass()
b=Myclass()
.
.
.
.
.
.

what's the easiest way to go about this?

thanks,
A