First rule of Python is - Everything in Python is an object

• Everything in Python is an object, and almost everything has attributes and methods.
• dir(object) to display the attributes and methods
• Everything can be assigned to a variable or passed as an argument to a function.
• Everything in Python has: an identity (id) and a value (mutable or immutable)

>>> id(a)
26165592
>>> 
>>> id(b)
26165592
>>> 
>>> a = 2
>>> 
>>> id(a)
26165568
>>> id(b)
26165592
>>>
>>> a = 10
>>> a -= 9
>>> a
1
>>> id(a)
26165592