code: def test_mul_zero_unknown(self):
      self.assertEqual(
          ValueRangeAnalysis.mul(
              ValueRanges.wrap(0), ValueRanges.unknown()
          ),
          ValueRanges.wrap(0),
      )
  
imports: import itertools
  import sys
  import sympy
  from typing import Callable, List, Tuple, Type
  from torch.testing._internal.common_device_type import skipIf
  from torch.testing._internal.common_utils import TEST_Z3, instantiate_parametrized_tests, parametrize, run_tests, TestCase
  from torch.utils._sympy.functions import FloorDiv
  from torch.utils._sympy.solve import INEQUALITY_TYPES, mirror_rel_op, try_solve
  from torch.utils._sympy.value_ranges import ValueRangeAnalysis, ValueRanges
  from torch.utils._sympy.reference import ReferenceAnalysis, PythonReferenceAnalysis
  from torch.utils._sympy.interp import sympy_interp
  from torch.utils._sympy.singleton_int import SingletonInt
  from sympy.core.relational import is_ge, is_le, is_gt, is_lt
  import functools
  import torch.fx
label_desc: Use image node_id 4 for calling the TestValueRanges obj's underlying member method code with example usage: obj.test_mul_zero_unknown() without return types