Noneis probably the most commonly assigned value in Python. But what happens if you move it to the left side of that equation?
In Python 2:
This is similar to what happens when you assign to a literal:
>>> None = 2 File "<stdin>", line 1 SyntaxError: cannot assign to None
In Python 3 this walk on the wild side will get you a slightly different error:
>>> 1 = 2 File "<stdin>", line 1 SyntaxError: can't assign to literal
>>> None = 1 File "<stdin>", line 1 SyntaxError: can't assign to keyword
Nonehas graduated from useful snowflake to full-blown keyword!