code: def test_mu3tet():
      assert intvol.mu3_tet(0, 0, 0, 0, 1, 0, 0, 1, 0, 1) == 1.0 / 6
      assert intvol.mu3_tet(0, 0, 0, 0, 0, 0, 0, 0, 0, 0) == 0
      d = [2, 2, 2]
      a = [3, 2, 2]
      b = [2, 3, 2]
      c = [2, 2, 3]
      assert pts2mu3_tet(d, a, b, c) == 1.0 / 6
      assert wiki_tet_vol(d, a, b, c) == 1.0 / 6
      # This used to generate nan values
      assert intvol.mu3_tet(0, 0, 0, 0, 1, 0, 0, -1, 0, 1) == 0
  
imports: from itertools import combinations
  import numpy
  import numpy.linalg
  import pytest
  from numpy.testing import assert_almost_equal, assert_array_equal
  from ..None import intvol
label_desc: Use image node_id 10 for calling a global function with example usage: test_mu3tet() without return types