private static List<KtFile> getSourceFiles(@NotNull Collection<KtNamedDeclaration> elementsToMove) {
        return CollectionsKt.distinct(
                CollectionsKt.map(
                        elementsToMove,
                        KtPureElement::getContainingKtFile
                )
        );
    }
private static List<KtFile> getSourceFiles(@NotNull Collection<KtNamedDeclaration> elementsToMove)