How do I change the camera automatically after a set timer?

Basically I want to start off with my overhead camera and then switch to my camera after 2 seconds, this is what I have so far.

public var OverheadCamera : Camera ;
public var SideCamera : Camera ;

function Update() {

if (Input.GetKey(KeyCode.X))
{
    OverheadCamera.GetComponent.<Camera>().enabled = true;
    SideCamera.GetComponent.<Camera>().enabled = false;
}


if (Input.GetKey(KeyCode.C))
{
    {
         yield WaitForSeconds(2);
    }
    OverheadCamera.GetComponent.<Camera>().enabled = false;
    SideCamera.GetComponent.<Camera>().enabled = true;
}

}

I believe yield WaitForSeconds does not work inside Function Update(), instead do something like this

public var OverheadCamera : Camera ; 
public var SideCamera : Camera ;

function Update() {

     if (Input.GetKey(KeyCode.X))
     {
         OverheadCamera.GetComponent.<Camera>().enabled = true;
         SideCamera.GetComponent.<Camera>().enabled = false;
     }
      
      
     if (Input.GetKey(KeyCode.C))
     {
      CameraSwap();
     }
}

function CameraSwap() {
         yield WaitForSeconds(2);
         OverheadCamera.GetComponent.<Camera>().enabled = false;
         SideCamera.GetComponent.<Camera>().enabled = true;
}