Why CodeChef is using Python 2.7.9 notwithstanding Python 2.7.11?

When I submitted my first solution(written in Python 2.7.13) to the CodeChef, it successfully get passed(100 marks).

After that I attempted 2nd problem and submitted my solution after a lot of tests with different test cases, now I am getting Wrong Answer.

Is it the problem of version or any other(As I have not tested it with Python 2.7.9).

I have tested my program number of times with different test cases.

I don’t think version should be a problem. Check you logic and code again.

if there is any problem with the version then you will get compilation error.If you get WA then i am pretty sure that that there is some mistake with your logic.

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