Pickle is likely still handy, as long as you created the data that you're deserializing. Zope's object database was a big pickle file, as I recall. But yeah, not a good idea if you're cracking open user-supplied files in any way.
That was my first web kind of framework. The naivette of Zope still amuses me endlessly to this very day.
It tried to be cool, made ALL the wrong choices, and died silently with people just moving on.
I will never recover from debugging ZODB backed by Oracle. Well, somewhat backed.
Who, like, who thought it was cool to have a pickle-based, mostly in-memory, single process, aaalmost transactional database?!
I was more traumatized by the Java-based product from Open Market (acquired from Future Tense back in the day), and all the horribleness that that entailed. Starting from XML as a template language, then seemed to get only worse. Nothing like having multiple content areas all rendered as 500 Server Error pages within one page, when it all goes sideways.