How to get the list of all initialized objects and function definitions alive in python?

Question

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 so

Answer 1

How about dir() which will output instantiated objects as a list? I just used this just now: [x for x in dir() if x.lower().startswith('y')]