code: def test_diag_plus_diag(self):
      diag1 = rng.rand(2, 3, 4)
      diag2 = rng.rand(4)
      op1 = linalg.LinearOperatorDiag(diag1)
      op2 = linalg.LinearOperatorDiag(diag2)
      hints = linear_operator_addition._Hints(
          is_positive_definite=True, is_non_singular=True
      )
  
      self.assertTrue(self._adder.can_add(op1, op2))
      operator = self._adder.add(op1, op2, "my_operator", hints)
      self.assertIsInstance(operator, linalg.LinearOperatorDiag)
  
      with self.cached_session():
          self.assertAllClose(
              linalg.LinearOperatorDiag(diag1 + diag2).to_dense(),
              operator.to_dense(),
          )
      self.assertTrue(operator.is_positive_definite)
      self.assertTrue(operator.is_non_singular)
      self.assertEqual("my_operator", operator.name)
  
imports: import numpy
  from tensorflow.python.framework import test_util
  from tensorflow.python.ops import linalg_ops
  from tensorflow.python.ops.linalg import linalg
  from tensorflow.python.ops.linalg import linear_operator_addition
  from tensorflow.python.platform import test
label_desc: Use image node_id 3 for calling the AddAndReturnDiagTest obj's underlying member method code with example usage: obj.test_diag_plus_diag() without return types