fact: Definition unorderedSequenceToFunction {X} (x:UnorderedSequence X) := pr2 x : pr1 (pr1 x) -> X.
imports: UniMath.Combinatorics.FiniteSets UniMath.Combinatorics.Lists UniMath.Combinatorics.Vectors UniMath.MoreFoundations.PartA UniMath.MoreFoundations.Tactics