ExtraCommands/extracommands/TestPatch.cs

using System;
using System.Reflection;
using Harmony;
using UnityEngine;

namespace TestMod
{
    [HarmonyPatch]
    class TestPatch
    {
        static void Prefix()
        {
            Debug.Log("Test Patch Prefix");
        }

        [HarmonyTargetMethod]
        static MethodBase HTargetMethod(HarmonyInstance instance)
        {
            throw new NotImplementedException();
        }
    }
}