Understanding Python's “is” operator

Question

The is operator does not match the values of the variables, but the instances themselves.

What does it really mean?

Answer 1

As you can check here to a small integers. Numbers above 257 are not an small ints, so it is calculated as a different object.

It is better to use == instead in this case.

Further information is here: http://docs.python.org/2/c-api/int.html