How do you control _all_ items added to a list?

[Xif]

Hi

I want to have control over all items added to a list.

The first attempt was to subclass list and override its .append()
method.

Problem is, there are plenty of other ways the list can have items
added to it - e.g. extend, insert - and theyr'e not at all affected by
the changes I made to append.

Is there some "base" item-adding method that all other item-adding
methods use, so I can override it and have the changes affect all
item-adding functions?

Thanks,
Xif