@Nullable
 public static FunctionDescriptor getOverriddenDescriptor(
     @NotNull FunctionDescriptor functionDescriptor) {
   Set<? extends FunctionDescriptor> overriddenDescriptors =
       functionDescriptor.getOverriddenDescriptors();
   if (overriddenDescriptors.isEmpty()) {
     return null;
   } else {
     // TODO: for now translator can't deal with multiple inheritance good enough
     return overriddenDescriptors.iterator().next();
   }
 }
 private static int valueParametersCount(@NotNull FunctionDescriptor functionDescriptor) {
   return functionDescriptor.getValueParameters().size();
 }