code: def test__mul__(parameter):
      """Test the __mul__ magic method."""
      par, _ = parameter
      assert_allclose(par * 2.5, 25.0)
      assert_allclose(par * -0.1, -1.0)
  
imports: from math import trunc
  import pickle
  import numpy
  from numpy.testing import assert_allclose
  import pytest
  import lmfit
label_desc: Use image node_id 37 for calling a global function with example usage: test__mul__(parameter) without return types