code: def test_product_leading_entries():
      """Tests product of leading entries method."""
      A, B = symbols("A, B")
  
      m1 = Matrix([[1, 2, 3], [0, 4, 5], [0, 0, 6]])
  
      m2 = Matrix([[0, 0, 1], [2, 0, 3]])
  
      m3 = Matrix([[0, 0, 0], [1, 2, 3], [0, 0, 0]])
  
      m4 = Matrix([[0, 0, A], [1, 2, 3], [B, 0, 0]])
  
      assert dixon.product_leading_entries(m1) == 24
      assert dixon.product_leading_entries(m2) == 2
      assert dixon.product_leading_entries(m3) == 1
      assert dixon.product_leading_entries(m4) == A * B
  
file_path: sympy/sympy/polys/tests/test_multivariate_resultants.py
imports: from sympy.matrices.dense import Matrix
  from sympy.polys.polytools import factor
  from sympy.core import symbols
  from sympy.tensor.indexed import IndexedBase
  from sympy.polys.multivariate_resultants import DixonResultant, MacaulayResultant
label_desc: Use image node_id 8 for calling a global function with example usage: test_product_leading_entries() without return types