code: func resourceVSphereLicenseUpdate(d *schema.ResourceData, meta interface{}) error {
  	log.Println("[INFO] Running the update method")
  
  	client := meta.(*VSphereClient).vimClient
  	manager := license.NewManager(client.Client)
  
  	if key, ok := d.GetOk("license_key"); ok {
  		licenseKey := key.(string)
  		if !isKeyPresent(licenseKey, manager) {
  			return ErrNoSuchKeyFound
  		}
  
  		if d.HasChange("labels") {
  			labelMap := d.Get("labels").(map[string]interface{})
  
  			err := updateLabels(manager, licenseKey, labelMap)
  			if err != nil {
  				return err
  			}
  		}
  	}
  
  	return resourceVSphereLicenseRead(d, meta)
  }
docs: // resourceVSphereLicenseUpdate check for change in labels of the key and updates them.