Implementation of NoneType, Reasons and Details

I recently read somewhere that the special value None in python is a singleton object of its own class, specifically NoneType. This explained a lot, since most errors involving None in python produce AttributeErrors instead of some special "NoneError" or something.

Since all of these AttributeErrors reflected the attributes that NoneType lacked, I became intrigued by what attributes NoneType did have, if any.

I decided to look into this NoneType and learn more about it. I've always found the best way to learn about a new language feature is to use it, so I tried instantiating NoneType in IDLE:

>>> n = NoneType()

This produced an error:

Traceback (most recent call last):
File "<pyshell#0>", line 1, in <module>
    n = NoneType()
NameError: name 'NoneType' is not defined

Confused, I inspected None to see if I'd gotten the type name correct. Sure enough,

>>> type(None)
<class 'NoneType'>

Now very confused, I did a quick google search. This revealed that for some reason NoneType was somehow removed in Python 3.

Well I though, ha ha! I can work around this by storing the type of None in a variable, since classes are objects in python. This seemed to work:

>>> NoneType = type(None)
>>> n = NoneType()

And when I printed n, I got pretty much what I was expecting:

>>> print(n)
None

But then this happened:

>>> n is None
True

And:

>>> id(n)
506768776
>>> id(None)
506768776

My variable n IS None. Not only the same type as None. It IS None. This is not what I expected.

I tried using dis to get more info on NoneType, but when I called

>>> dis.dis(type(None))

It produced no output.

I then then tried investigating the __new__ method, which several users had mentioned in the comments:

dis.dis(type(None).__new__)
Traceback (most recent call last):
  File "<pyshell#4>", line 1, in <module>
    dis.dis(type(None).__new__)
  File "C:\Python33\lib\dis.py", line 59, in dis
    type(x).__name__)
TypeError: don't know how to disassemble builtin_function_or_method objects
>>> 

More errors.

Here are my questions:

• Why is n the exact same Object as None?
• Why was the language designed such that n is the exact same Object as None?
• How would one even implement this behavior in python?