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Python id and '__main__' are different

Usually, if I assign a value to a variable and then check their identifiers, I expect them to be the same, because python essentially just gives my object a "name". This can be seen in the code below:

>>> a = 3
>>> id(a)
19845928
>>> id(3)
19845928

The problem is that I am doing the same thing with the name 

>>> __name__
'__main__'
>>> id(__name__)
19652416
>>> id('__main__')
19652448

How can identifiers be different, should they not be the same? Because it __name__should also be just a link.

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4 answers

id () gives essentially a memory pointer to data. Although the strings are immutable, they do not guarantee internment. This means that some lines with equal values ​​have different pointers.

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>>> __name__
'__main__'
>>> x = __name__
>>> id(__name__)
3078339808L
>>> id(x)
3078339808L
>>> __name__ is x
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