study/first_study/Library/PackageCache/com.unity.timeline@7f8b2fb101b6/Runtime/Extensions/SelectionExtensions.cs

namespace UnityEngine.Timeline
{
    static class SelectionExtensions
    {
        public static ObjectId GetObjectId(this Object obj)
        {
#if UNITY_6000_3_OR_NEWER
            return obj.GetEntityId();
#else
            return obj.GetInstanceID();
#endif
        }
    }
}