title: Cant get script in custom inspector if it don't inherit anything
body: <p>i have a problem, and i have no idea how to solve it. So i have a custom inspector, and i want to make on a class which has no inhert, like a custom variable. Here i will show the code and hopefully you understand</p>
  
  <pre><code>using System.Collections.Generic;
  using System.Collections;
  using UnityEngine;
  using UnityEditor;
  
  [CustomEditor(typeof(QuizHolder))]
  public class QuizHolderInspector : Editor {
      public override void OnInspectorGUI()
      {
          QuizHolder myScript = (QuizHolder)target;//This produces a squigly line, and makes the error : "Cannot convert type 'UnityEngine.Object' to 'QuizHolder'"
          MakePublic("m_Script");
          MakePublic("NameOfQuizHolder");
          MakePublic("Whichquiz");
          //if (qui == QuizHolder.WhichQuiz.NumberQuiz)
          //{
  
          //}
      }
      void MakePublic(string smart)
      {
          var property2 = serializedObject.FindProperty(smart);
          serializedObject.Update();
          EditorGUILayout.PropertyField(property2, true);
          serializedObject.ApplyModifiedProperties();
      }
  }`
  </code></pre>
  
  <p>also the quizholder code is :`</p>
  
  <pre><code>using System.Collections;
  using System.Collections.Generic;
  using UnityEngine;
  [System.Serializable]
  public class QuizHolder {//As you see here, it doesnt inherit monodevolep, and i think that is the problem, but i don't know how to fix it since i need it to not inherit monodevolep
      public string NameOfQuizHolder;
      public enum WhichQuiz {NumberQuiz,OptionQuiz,InputFieldQuiz};
      public WhichQuiz Whichquiz;
      public NumberQuiz Numberquiz;
      public OptionQuiz Optionquiz;
      public InputFieldQuiz InputFieldquiz;
  }`
  </code></pre>
  
  <p>please help me, i am a bit tired so sorry if it doesnt make sense.
  Thanks</p>