Understanding object model and bytecode is a crucial part in understanding an interpreted object-oriented language. Smalltalk, one of the oldest object-oriented programming languages, has a great object model and has been used bytecode and VM since 1970s. It is interesting to compare Smalltalk's and Python's object model and bytecode. Guido once said "I remember being surprised by its use of metaclasses (which is quite different from that in Python or Ruby!) when I read about them much later. " and "Smalltalk's bytecode was a bigger influence of Python's bytecode though." It is interesting to compare Smalltalk's and Python's metacalss and bytecode.