Python Boolean Logic Confusion

Question

Can someone clarify the logic behind these assignment statements.

>>> True
True
>>> True = False
>>> True
False
>>> True = True
>>> True
False
>>> a = True
>>> if a:
...     print "a is True"
... else:
...     print "a is False"
...
a is False

According to the manual, the only two instances of class bool is True and False.

Help on bool object:

True = class bool(int)
 |  bool(x) -> bool
 |
 |  Returns True when the argument x is true, False otherwise.
 |  The builtins True and False are the only two instances of the class bool.
 |  The class bool is a subclass of the class int, and cannot be subclassed.
 |
 |  Method resolution order:
 |      bool
 |      int
 |      object

So am I overriding the default instance? And if so, why does python does not assign True to is default instance in the below assignment? How can I assign the default python True in the below statement?

>>> True = False
>>> True
False
>>> True = True
>>> True
False     #why?

Thanks in advance for any help!!!

Python 3 tag is irrelevant here: [Why were True and False changed to keywords in Python 3](http://stackoverflow.com/questions/18050815/why-were-true-and-false-changed-to-keywords-in-python-3) — awesoon, Apr 21 '16 at 07:07
It does, but I thought you were trying to compare in the lines above that, maybe I misunderstood. — RemcoGerlich, Apr 21 '16 at 07:22

score 0 · Answer 1 · answered Apr 21 '16 at 07:06

0

When you do:

True = False

True becomes False.. And when you do:

True = True

It's like writing:

True = False

If you want to make it the "original" True again, you should:

>>> True = not True # recall that you assigned False to True
>>> True
True

answered Apr 21 '16 at 07:06

Maroun

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`del True` is a better way to delete the local variable named `True`, making the builtin one visible again. – RemcoGerlich Apr 21 '16 at 07:12
how can we access the built-in True in python? It seems you are performing 'not' operation on the local variable 'True' from your answer... – TerminalWitchcraft Apr 21 '16 at 07:17
@HiteshPaul It'll become the "built in" `True`. – Maroun Apr 21 '16 at 07:20

Python Boolean Logic Confusion

1 Answers1