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Javascript last non-random test:
says [1,null,1,2,null,2,null] should stay as it is.
instead of [1,1,1,2,2,2,null] like in other tests.
example:
Random input: [3,null,null,4,3,null,3,4,null,null,2,2,null,null,null]
Test Passed: Value == [3,null,null,4,3,3,3,4,null,null,2,2,null,null,null] // note that input[5] changes

Seems like an error

I have problems with the kata tests.
The test returns Uknown error. I test the kata in Jsbin and works fine.
Any idea?

Please include Python3 ;D