Question5_practical.cs

using UnityEngine;

public class Question5_practical : MonoBehaviour {

}

Question5Editor_practical.cs

using UnityEditor;
using UnityEngine;

public class Question5Editor_practical
{
    [DrawGizmo(GizmoType.NotSelected | GizmoType.Selected)]
    static void OnDrawGizmos(Question5_practical target, GizmoType type)
    {
        Collider[] overlapSphere = Physics.OverlapSphere(target.transform.position, 0.1f);

        if (overlapSphere.Length != 0)
        {
            Gizmos.color = Color.red;
        }
        Gizmos.DrawWireSphere(target.transform.position, 0.1f);
    }
}