code: def test_untracking_in_tracked_list(self):
      tracked_variables = []
      tracker = tracking.Tracker(
          {
              "variables": (
                  lambda x: isinstance(x, backend.Variable),
                  tracked_variables,
              ),
          }
      )
      v1 = backend.Variable(1)
      v2 = backend.Variable(2)
      lst = tracking.TrackedList([], tracker)
      lst.append(v1)
      lst.append(None)
      lst.append(v2)
      lst.append(0)
  
      self.assertLen(tracked_variables, 2)
      self.assertEqual(tracked_variables[0], v1)
      self.assertEqual(tracked_variables[1], v2)
  
      lst.remove(v1)
      self.assertLen(lst, 3)
      self.assertLen(tracked_variables, 1)
  
      lst.remove(v2)
      self.assertLen(lst, 2)
      self.assertLen(tracked_variables, 0)
  
      lst2 = tracking.TrackedList([], tracker)
      lst2.append(v1)
      lst2.append(None)
      lst2.append(v2)
      lst2.append(0)
  
      popped_value = lst2.pop()
      self.assertEqual(popped_value, 0)
      self.assertLen(lst2, 3)
      self.assertLen(tracked_variables, 2)
  
      lst2.clear()
      self.assertLen(lst2, 0)
      self.assertLen(tracked_variables, 0)
  
      lst2.append(v1)
      lst2.append(v2)
      del lst2[0]
      self.assertLen(lst2, 1)
      self.assertLen(tracked_variables, 1)
  
imports: from keras import backend
  from keras import testing
  from keras.utils import tracking
label_desc: Use image node_id 1 for calling the TrackingTest obj's underlying member method code with example usage: obj.test_untracking_in_tracked_list() without return types