The type or namespace name 'SerializedFieldAttribute' could not be found

Assets\Enemy.cs(5,6): error CS0246: The type or namespace name 'SerializedFieldAttribute' could not be found (are you missing a using directive or an assembly reference?)

This is the error I have been receiving. It seems like when I add the [SerializedField] maybe my VScode isn't recognizing it. Can someone please take a look at my code and see if they can spot anything I could be missing. I have been following a tutorial all day and it has gone fine up until this point. I have rewritten the code from scratch and copied each line character by character and I still cannot get the particle system to function.

Code (CSharp):

1. using UnityEngine;
2.  
3. public class Enemy : MonoBehaviour
4. {
5.     [SerializedField] private GameObject _cloudParticlePrefab;
6.  
7.     private void OnCollisionEnter2D(Collision2D collision)
8.     {
9.         Bird bird = collision.collider.GetComponent<Bird>();
10.         if (bird != null)
11.         {
12.             Instantiate(_cloudParticlePrefab, transform.position, Quaternion.identity);
13.             Destroy(gameObject);
14.             return;
15.         }
16.  
17.         Enemy enemy = collision.collider.GetComponent<Enemy>();
18.         if (enemy != null)
19.         {
20.             return;
21.         }
22.  
23.         if( collision.contacts[0].normal.y < -0.5)
24.         {
25.             Instantiate(_cloudParticlePrefab, transform.position, Quaternion.identity);
26.             Destroy(gameObject);
27.         }
28.     }
29. }

 

It's SerializeField, not SerializedField. No 'd'.

 

Thank you I knew I was messing something up and I was just overlooking it! I really appreciate your help!

 

its serializefield without d