How to set GameObject created by MenuItem as a child of Canvas

Hi i need help how can i set the gameobject created by menuitem as a child of canvas

     [MenuItem("GameObject/UI/Custom Button", false, 10)]
     static void CreateCustomButton(MenuCommand menuCommand)
     {
         GameObject custombutton = 
         (GameObject)PrefabUtility.InstantiatePrefab(AssetDatabase.LoadAssetAtPath<Object> 
         ("Assets/Prefabs/CustomButton.prefab"));
 
         Undo.RegisterCreatedObjectUndo(custombutton, "Create " + custombutton.name);
         Selection.activeObject = custombutton;
     }