Your solution is very short, but is not effective. Because, to calculate one permutation, the algorithm will calculate all possible permutations and return one.

Clever use of Python's built-in itertools module - you successfully reduced the code in the original Kumite from an entire class to a single method utilizing a simple built-in method :) In response to your concern regarding the purpose of Kumite, don't worry - you've got it absolutely correct :D However, while Python classes are in PascalCase by convention, Python methods (and variables) should always be in snake_case as per PEP 8 so your SequencePermutation method should be renamed to sequence_permutation.