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i guess that is true in python3 but it is not in python 2.7.



False. You're just not familiar with how the REPL works.

    >>> None
    >>> print(None)
    None

In the future, you might want to refrain from strong criticism of a thing you're not familiar with. That habit leads to all sorts of -isms.


i do know how the repl works. i explicitly tried it out. i defined the function just as i said and ran

  test(2) is None
and got false. i just now went to try it out again at home and got true. i don't know what to tell you other than something must have got shadowed somewhere.


Here's what I get from the Python 3 REPL:

    peter@localhost:~$ python3
    Python 3.5.2 (default, Nov 23 2017, 16:37:01)
    [GCC 5.4.0 20160609] on linux
    Type "help", "copyright", "credits" or "license" for more information.
    >>> def test(x):
    ...     "something"
    ...
    >>> test(2) is None
    True
And Python 2:

    peter@localhost:~$ python
    Python 2.7.12 (default, Dec  4 2017, 14:50:18)
    [GCC 5.4.0 20160609] on linux2
    Type "help", "copyright", "credits" or "license" for more information.
    >>> def test(x):
    ...     "something"
    ...
    >>> test(2) is None
    True
If you post such a transcript from your REPL session where you get False, it should be easier to tell what's different between your setup and mine (which is a stock Python install on Ubuntu 16.04).

However, there is another even more direct experiment you could have run at the Python REPL to see what Python expressions return: just type the expression directly at the REPL and see what it prints back at you. In Python 3:

    peter@ToshibaSatellite:~$ python3
    Python 3.5.2 (default, Nov 23 2017, 16:37:01)
    [GCC 5.4.0 20160609] on linux
    Type "help", "copyright", "credits" or "license" for more information.
    >>> "something"
    'something'
And in Python 2:

    peter@ToshibaSatellite:~$ python
    Python 2.7.12 (default, Dec  4 2017, 14:50:18)
    [GCC 5.4.0 20160609] on linux2
    Type "help", "copyright", "credits" or "license" for more information.
    >>> "something"
    'something'
So, in your test function above, the expression "something" does return itself; it just does it inside the function, and that return value then gets thrown away when the function exits, because you didn't return it from the function itself.


i know how to use the repl. i moved between computers during comments and wasn't able to inspect my repl session where it originally returned false. as i mentioned, i must have redefined something or shadowed something which caused confusion, and i just didn't realize it at the time.




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