Q: When and why to use dynamic variables?

[Robb Shecter]

Hi,

I'm looking for more information about the ability in Python to add
variables to an object instance at runtime.  I'm interested in both
the theoretical as well as practical implications of this feature.

Can anyone point me to information about it?  For example, code where
this feature is used, descriptions of it, suggested uses, etc.

Thanks,
Robb