code: def test_empty(self):
      a, b = histogramdd([[], []], bins=([0, 1], [0, 1]))
      # assert_array_max_ulp(a, np.array([[0.]]))
      assert_allclose(a, np.array([[0.0]]), atol=1e-15)
      a, b = np.histogramdd([[], [], []], bins=2)
      # assert_array_max_ulp(a, np.zeros((2, 2, 2)))
      assert_allclose(a, np.zeros((2, 2, 2)), atol=1e-15)
  
imports: import functools
  from unittest import expectedFailure, skipIf
  from pytest import raises
  from torch.testing._internal.common_utils import instantiate_parametrized_tests, parametrize, run_tests, slowTest, TEST_WITH_TORCHDYNAMO, TestCase, xpassIfTorchDynamo
label_desc: Use image node_id 6 for calling the TestHistogramdd obj's underlying member method code with example usage: obj.test_empty() without return types