code: def test_empty(self):
      a, b = histogramdd([[], []], bins=([0, 1], [0, 1]))
      assert_array_max_ulp(a, np.array([[0.0]]))
      a, b = np.histogramdd([[], [], []], bins=2)
      assert_array_max_ulp(a, np.zeros((2, 2, 2)))
  
imports: import numpy
  from numpy import histogram, histogramdd, histogram_bin_edges
  from numpy.testing import assert_, assert_equal, assert_array_equal, assert_almost_equal, assert_array_almost_equal, assert_raises, assert_allclose, assert_array_max_ulp, assert_raises_regex, suppress_warnings
  from numpy.testing._private.utils import requires_memory
  import pytest
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