code: def test_empty_indices(self):
      msg1 = "indices must be integral: the provided empty sequence was"
      msg2 = "only int indices permitted"
      assert_raises_regex(
          TypeError, msg1, np.unravel_index, [], (10, 3, 5)
      )
      assert_raises_regex(
          TypeError, msg1, np.unravel_index, (), (10, 3, 5)
      )
      assert_raises_regex(
          TypeError, msg2, np.unravel_index, np.array([]), (10, 3, 5)
      )
      assert_equal(
          np.unravel_index(np.array([], dtype=int), (10, 3, 5)),
          [[], [], []],
      )
      assert_raises_regex(
          TypeError, msg1, np.ravel_multi_index, ([], []), (10, 3)
      )
      assert_raises_regex(
          TypeError, msg1, np.ravel_multi_index, ([], ["abc"]), (10, 3)
      )
      assert_raises_regex(
          TypeError,
          msg2,
          np.ravel_multi_index,
          (np.array([]), np.array([])),
          (5, 3),
      )
      assert_equal(
          np.ravel_multi_index(
              (np.array([], dtype=int), np.array([], dtype=int)), (5, 3)
          ),
          [],
      )
      assert_equal(
          np.ravel_multi_index(np.array([[], []], dtype=int), (5, 3)),
          [],
      )
  
imports: import pytest
  import numpy
  from numpy.testing import assert_, assert_equal, assert_array_equal, assert_almost_equal, assert_array_almost_equal, assert_raises, assert_raises_regex
  from numpy.lib.index_tricks import mgrid, ogrid, ndenumerate, fill_diagonal, diag_indices, diag_indices_from, index_exp, ndindex, r_, s_, ix_
label_desc: Use image node_id 2 for calling the TestRavelUnravelIndex obj's underlying member method code with example usage: obj.test_empty_indices() without return types