@NotNull
 private Set<PsiPackage> getContext() {
   if (myIndex == 0) return myReferenceSet.getInitialContext();
   Set<PsiPackage> psiPackages = new HashSet<>();
   for (ResolveResult resolveResult : myReferenceSet.getReference(myIndex - 1).doMultiResolve()) {
     PsiElement psiElement = resolveResult.getElement();
     if (psiElement instanceof PsiPackage) {
       psiPackages.add((PsiPackage) psiElement);
     }
   }
   return psiPackages;
 }