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python - Why does `False is False is False` evaluate to `True`?

Why in Python it is evaluated this way:

>>> False is False is False
True

but when tried with parenthesis is behaving as expected:

>>> (False is False) is False
False
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Chaining operators like a is b is c is equivalent to a is b and b is c.

So the first example is False is False and False is False, which evaluates to True and True which evaluates to True

Having parenthesis leads to the result of one evaluation being compared with the next variable (as you say you expect), so (a is b) is c compares the result of a is b with c.


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