code: def test_metrics_mul(second_operand, expected_result):
      """Test that `mul` operator works and returns a compositional metric."""
      first_metric = DummyMetric(2)
  
      final_mul = first_metric * second_operand
      final_rmul = second_operand * first_metric
  
      assert isinstance(final_mul, CompositionalMetric)
      assert isinstance(final_rmul, CompositionalMetric)
  
      final_mul.update()
      final_rmul.update()
      assert torch.allclose(expected_result, final_mul.compute())
      assert torch.allclose(expected_result, final_rmul.compute())
  
imports: from operator import neg, pos
  from typing import Any
  import pytest
  import torch
  from torch import tensor
  from torchmetrics.metric import CompositionalMetric, Metric
label_desc: Use image node_id 11 for calling a global function with example usage: test_metrics_mul(second_operand, expected_result) without return types