I would like to give some feedback about ...

From: http://www.checkio.org/mission/place-queens/solve/

In case when my function should return empty set i get error type - despite that I convert returned variable into set! I tried: K=[] K=set(K) return K

K=[] K=set(K) return set(K)

K=[] return set(K)

K=set() return K

return set()

But nothing works!

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