unity freezes when opening script code example

Example: unity freeze position in script

using UnityEngine;

public class FreezePosition : MonoBehaviour
{
    public GameObject TheThingToFreeze;
  	
    public void	Start()
    {
    	TheThingToFreeze.GetComponent<Rigidbody>().constraints = RigidbodyConstraints.FreezePositionX | RigidbodyConstraints.FreezePositionY | RigidbodyConstraints.FreezePositionZ;  
    }
      
}