@NotNull
  public static List<PsiMethod> getPossibleMethods(@NotNull Set<? extends PsiClass> classes, @NotNull String name, int callArgCount) {
    return ContainerUtil.flatMap(classes,
      aClass -> ContainerUtil.filter(aClass.findMethodsByName(name, true), m->canHaveArgCount(m, callArgCount)));
  }
@NotNull
  public static List<PsiMethod> getPossibleMethods(@NotNull Set<? extends PsiClass> classes, @NotNull String name, int callArgCount)