Given a Python class which will be instantiated only once, i.e. there will be only one object of the class. I was wondering in which cases it makes sense to create a single class instance instead of working directly with the class instead. 

There is a similar [question][1], but it has a different focus: 

1. it is about grouping global variables and functions into a class and 
2. It isn't Python-specific. The latter means it does not consider the fact that (in Python) classes are objects too.


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**UPDATE:**

In Python, I can do the following with both classes and objects:

    class A(object):
        pass

    A.some_state_var = True
    # Then later
    A.some_state_var = False


    my_a = A()
     
    my_a.some_state_var = True
    # Then later
    my_a.some_state_var = False

So I don't see how the choice between a class and an instance of that class is about state (in Python). I can maintain a state with either of the two.

Furthermore, the motivation to create my class / class instance is not about enforcing a Singleton requirement.

Also, it is not so much about creating a new Type.

The motivation is to group related code and data and having an interface to it. This is why I modeled it as a class in a class diagram. Only when it came to the implementation I started wondering during implementation whether to instantiate this class or not.

  [1]: http://programmers.stackexchange.com/questions/213343/is-it-a-bad-idea-to-create-a-class-which-will-only-have-one-instance