double equals vs is in python

python comparison boolean equals equality
ben picture ben · Feb 21, 2013 · Viewed 89k times · Source

I run the following in the Python interpreter:

>>> foo = 10
>>> dir(foo) == dir(10)
True
>>> dir(foo) is dir(10)
False
>>>

Why is this?

Answer

Silas Ray picture Silas Ray · Feb 21, 2013

is checks that 2 arguments refer to the same object, == checks that 2 arguments have the same value. dir() returns a list which contains the same data for both foo and 10, but the actual list instances for the 2 things are different.

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