new_contents: import pytest
  
  from .common import *  # NOQA
  
  def test_add_node_label():
      client, cluster = get_global_admin_client_and_cluster()
      test_label = "foo"
      nodes = client.list_node(clusterId=cluster.id)
      assert len(nodes.data) > 0
      node_id = nodes.data[0].id
      node = client.by_id_node(node_id)
  
      # Make sure there is no test label and add test label
      node_labels = node.labels.data_dict()
      assert test_label not in node_labels
  
      node_labels[test_label] = "bar"
      client.update(node, labels=node_labels)
  
      # Label should be added
      wait_for_condition(client, node, check_label_added(test_label), None, 10)
      node = client.reload(node)
      node_labels = node.labels.data_dict()
      assert node_labels[test_label] == "bar"
  
       # Label should be delete
      del node_labels[test_label]
      client.update(node, labels=node_labels)
      wait_for_condition(client, node, check_label_removed(test_label), None, 10)
      node = client.reload(node)
      node_labels = node.labels.data_dict()
      assert test_label not in node_labels
  
  def check_label_added(test_label):
      def _find_condition(resource):
          node_labels = resource.labels.data_dict()
  
          if test_label in node_labels:
              return True
          else: 
              return False 
  
      return _find_condition
  
  def check_label_removed(test_label):
      def _find_condition(resource):
          node_labels = resource.labels.data_dict()
  
          if test_label not in node_labels:
              return True
          else: 
              return False 
  
      return _find_condition
subject: Add validation test for adding node label