code: def test__neg__(parameter):
      """Test the __neg__ magic method."""
      par, _ = parameter
      assert_allclose(-par, -10.0)
      par.set(value=-10.0)
      assert_allclose(-par, 10.0)
  
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 25 for calling a global function with example usage: test__neg__(parameter) without return types