14.7: Classes as Types

As we have seen, in Python, all variables have a type. And we can use the built-in dir function to examine the capabilities of a variable. We can use type and dir with the classes that we create.

%%python3

class PartyAnimal:
   x = 0

   def party(self) :
     self.x = self.x + 1
     print(\"So far\",self.x)

an = PartyAnimal()
print (\"Type\", type(an))
print (\"Dir \", dir(an))
print (\"Type\", type(an.x))
print (\"Type\", type(an.party))

# Code: http://www.py4e.com/code3/party3.py

When this program executes, it produces the following output:

Type <class '__main__.PartyAnimal'>
Dir  ['__class__', '__delattr__', ...
'__sizeof__', '__str__', '__subclasshook__',
'__weakref__', 'party', 'x']
Type <class 'int'>
Type <class 'method'>

You can see that using the class keyword, we have created a new type. From the dir output, you can see both the x integer attribute and the party method are available in the object.