docstr: Tests order_by_dependency correctness.
docstr_tok: ["Tests","order_by_dependency","correctness","."]
code: def test_order_by_dependency(self):
      """Tests order_by_dependency correctness."""
  
      # Visual graph (vertical lines point down, so 1 depends on 2):
      #    1
      #  /   \
      # 2 --> 3 <-- 4
      #       |
      #       5
      # One possible order: [5, 3, 4, 2, 1]
      dependencies = {1: [2, 3], 2: [3], 3: [5], 4: [3], 5: []}
  
      sorted_arr = list(
          trackable_utils.order_by_dependency(dependencies)
      )
      indices = {x: sorted_arr.index(x) for x in range(1, 6)}
      self.assertEqual(indices[5], 0)
      self.assertEqual(indices[3], 1)
      self.assertGreater(indices[1], indices[2])
  
imports: from tensorflow.python.eager import test
  from tensorflow.python.trackable import trackable_utils
label_desc: Use image node_id 1 for calling the TrackableUtilsTest obj's underlying member method code with example usage: obj.test_order_by_dependency() without return types