Foreach in coroutine (Really need a reply!)

The Newbies Fail: Chapter One

I'm kinda noob in scripting so i have this problem: Ok, I want to deselect (play function Deselected) on script of a found object with tag "Forest Union" but i have cought this error:

`PlayerControls.GetEnumerator()' must have a body because it is not marked abstract, extern, or partial

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And I realy don't know what to do, i was looking for information on many forums, but no result! Please help! Here's my script:

 using UnityEngine;
 using System.Collections;
 
 public class PlayerControls : MonoBehaviour {
 
     [SerializeField]
     private LayerMask clickablesLayer;
     public Camera raycaster;
     public GameObject[] yourUnits;
     private GameObject unit;
     private IEnumerator coroutine;
     [SerializeField]
     private string factionTag;
 
     void Update () {
         
         if (Input.GetButtonDown("LeftMouse"))
         {
             StartCoroutine("DeselectAll");
 
             RaycastHit rayHit;
 
             if (Physics.Raycast(raycaster.ScreenPointToRay(Input.mousePosition), out rayHit, Mathf.Infinity, clickablesLayer))
             {
                 if (rayHit.collider.GetComponent<UnitStats>().FactionForestUnion)
                 {
                     rayHit.collider.GetComponent<UnitControls>().Clicked();
                 }
 
             }
         }
 
     }
 
     IEnumerator DeselectAll()
     {
         yield return new WaitForSeconds(0.0f);
         GameObject yourUnits = GameObject.FindGameObjectWithTag (factionTag);
         foreach (GameObject unit in yourUnits)
         {
             unity.GetComponent<UnitControls>().Deselected();
         }
     }
 }

Really hope someone would help me, I need reply very fast and soon!