text: import ubermagutil.units as uu
  
  
  def test_multiplier():
      assert uu.si_multiplier(1e-9) == 1e-9
      assert uu.si_multiplier(50e-9) == 1e-9
      assert uu.si_multiplier(100e-9) == 1e-9
      assert uu.si_multiplier(-100e-9) == 1e-9
      assert uu.si_multiplier(1001e-9) == 1e-6
      assert uu.si_multiplier(0) == 1
      assert uu.si_multiplier(1e3) == 1e3
      assert uu.si_multiplier(0.5e-9) == 1e-12
      assert uu.si_multiplier(0.5) == 1e-3
      assert uu.si_multiplier(0.05) == 1e-3
      assert uu.si_multiplier(5) == 1
      assert uu.si_multiplier(50) == 1
      assert uu.si_multiplier(500) == 1
      assert uu.si_multiplier(5e30) is None
  
  
  def test_si_max_multiplier():
      values = (5e-10, 6e-09, 4e-09)
      assert uu.si_max_multiplier(values) == 1e-9
      values = (1, 1e-3, 1e-6)
      assert uu.si_max_multiplier(values) == 1
      values = (1, 1e3, 1e6)
      assert uu.si_max_multiplier(values) == 1e6
  