Say that in the python shell (IDLE) I have defined some classes, functions, variables. Also created objects of the classes. Then I deleted some of the objects and created some others. At a later point in time, how can I get to know what are the currently active objects, variables, and methods definitions active in the memory?
Yes.
>>> import gc
>>> gc.get_objects()
Not that you'll find that useful. There is a lot of them. :-) Over 4000 just when you start Python.
Possibly a bit more useful is all the variables active locally:
>>> locals()
And the one active globally:
>>> globals()
(Note that "globally" in Python isn't really global as such. For that, you need the gc.get_objects()
above, and that you are unlikely to ever find useful, as mentioned).