how to set transform parent in unity code example

Example: setparent unity

using UnityEngine;public class ExampleClass : MonoBehaviour
{
    public GameObject child;    public Transform parent;    //Invoked when a button is clicked.
    public void Example(Transform newParent)
    {
        // Sets "newParent" as the new parent of the child GameObject.
        child.transform.SetParent(newParent);        // Same as above, except worldPositionStays set to false
        // makes the child keep its local orientation rather than
        // its global orientation.
        child.transform.SetParent(newParent, false);        // Setting the parent to ‘null’ unparents the GameObject
        // and turns child into a top-level object in the hierarchy
        child.transform.SetParent(null);
    }
}