Class and object namespaces

After the class object has been created (which usually happens when the module is first imported), it basically represents a namespace. We can call that class to create its instances. Each instance inherits the class attributes and methods and is given its own namespace. We already know that, to walk a namespace, all we need to do is to use the dot (.) operator.

Let's look at another example:

# oop/class.namespaces.py
class Person:
    species = 'Human'

print(Person.species)  # Human
Person.alive = True  # Added dynamically!
print(Person.alive)  # True

man = Person()
print(man.species)  # Human (inherited)
print(man.alive)  # True (inherited)

Person.alive = False
print(man.alive)  # False (inherited)

man.name = 'Darth'
man.surname = 'Vader'
print(man.name, man.surname)  # Darth Vader

In the preceding example, I have defined a class attribute called species. Any variable defined in the body of a class is an attribute that belongs to that class. In the code, I have also defined Person.alive, which is another class attribute. You can see that there is no restriction on accessing that attribute from the class. You can see that man, which is an instance of Person, inherits both of them, and reflects them instantly when they change.

man has also two attributes that belong to its own namespace and therefore are called instance attributes: name and surname.