Create script with custom template

Question

I need to make the following as the default template of my new C# scripts added in Unity Editor.

using System.Collections;
using System.Collections.Generic;         


        

Answer 1

I checked that but there's no problem.

Check This Point

1. Is AddNameSpace class in the Assets/Editor in project?

2. If you develop CS, modify 81-C# Script-NewBehaviourScript.cs in Unity\Editor\Data\Resources\ScriptTemplates