class Classname(object), what sort of word is 'object' in Python?

Question

When I create a module with its sole content:

class Classname(randomobject):     pass 

And I try to run the .py file of the module the interpreter says that randomobject is not defined.

But when I do:

class Classname(object):     pass 

The module runs just fine. So if object is not a keyword, then what is it?

Answer 1

object is a (global) variable. By default it is bound to a built-in class which is the root of the type hierarchy.

(This leads to the interesting property that you can take any built-in type, and use the __bases__ property to reach the type called object).

Everything built-in that isn't a keyword or operator is an identifier.

Answer 2

The following three class declarations are identical in Python 3

class Classname(object):     pass  class Classname():     pass  class Classname:     pass 

Well, there will be minor differences, but not fundamentally important since the object class is the base for all.

If you plan to write Python agnostic code (Python2 and Python3 agnostic) you may use the first declaration.