old_contents: from __future__ import division
  
  from nose.tools import assert_is_instance
  
  from dit import Distribution, ScalarDistribution
  from dit.convert import DtoSD, SDtoD
  
  def test_DtoSD():
      outcomes = ['00', '01', '10', '11']
      pmf = [1/4]*4
      d = Distribution(outcomes, pmf)
      sd = DtoSD(d, False)
      assert(type(d) is Distribution)
      assert(type(sd) is ScalarDistribution)
  
  def test_SDtoD():
      sd = ScalarDistribution([1/4]*4)
      d = SDtoD(sd)
      assert(type(sd) is ScalarDistribution)
      assert(type(d) is Distribution)
new_contents: from __future__ import division
  
  from dit import Distribution, ScalarDistribution
  from dit.convert import DtoSD, SDtoD
  
  def test_DtoSD():
      outcomes = ['00', '01', '10', '11']
      pmf = [1/4]*4
      d = Distribution(outcomes, pmf)
      sd = DtoSD(d, False)
      assert(type(d) is Distribution)
      assert(type(sd) is ScalarDistribution)
  
  def test_SDtoD():
      sd = ScalarDistribution([1/4]*4)
      d = SDtoD(sd)
      assert(type(sd) is ScalarDistribution)
      assert(type(d) is Distribution)
subject: remove the import too