The [] lead to list comprehension which will actually create the array. Omitting [] is the same as replacing it by (). That is a generator expression, which does not construct the array first and should therefore be preferred.

You are right, the brackets are not needed. Further, they are not wanted - the code would be better (clearer and more efficient) without them.

hmm, did sanme without list brakets. is it only for v3 or it didnot even need [] ?