code: def test_nested():
      msg = ""
      try:
          B()
      except BaseException as e:
          msg = e.args[0]
  
      expected = (
          "matmul: Input operand 1 has a mismatch in its core dimension 0, with gufunc signature (n?,k),(k,m?)->(n?,m?) (size 2 is different from 1)\n"
          + "Cause: @ on tensor operand np.ones(1) w/shape (1,) and operand np.ones(2) w/shape (2,)"
      )
      assert msg == expected
  
imports: import tsensor
  import numpy
label_desc: Use image node_id 4 for calling a global function with example usage: test_nested() without return types