old_contents: """Test CoolProp interaction."""
  
  import CoolProp
  
  import pygaps
  
  
  class TestCoolProp():
      """Test CoolProp interaction."""
  
      def test_backend_change(self):
          """Test if backend can change."""
          previous_backend = pygaps.COOLPROP_BACKEND
          pygaps.backend_use_refprop()
          assert previous_backend != pygaps.COOLPROP_BACKEND
          pygaps.backend_use_coolprop()
          assert previous_backend == pygaps.COOLPROP_BACKEND
  
      def test_backend_names_coolprop(self):
          """Test if CoolProp can be called for database adsorbents."""
          for adsorbate in pygaps.ADSORBATE_LIST:
              try:
                  adsorbate.backend.molar_mass()
              except pygaps.utilities.exceptions.ParameterError:
                  pass
  
      def test_backend_names_refprop(self):
          """Test if RERFPROP can be called for database adsorbents."""
          version = CoolProp.CoolProp.get_global_param_string("REFPROP_version")
          if version:
              print(version)
              pygaps.backend_use_refprop()
              for adsorbate in pygaps.ADSORBATE_LIST:
                  print(adsorbate)
                  try:
                      adsorbate.backend.molar_mass()
                  except pygaps.utilities.exceptions.ParameterError:
                      pass
              pygaps.backend_use_coolprop()
  
new_contents: """Test CoolProp interaction."""
  
  import CoolProp
  
  import pygaps
  
  
  class TestCoolProp():
      """Test CoolProp interaction."""
  
      def test_backend_change(self):
          """Test if backend can change."""
          previous_backend = pygaps.COOLPROP_BACKEND
          pygaps.backend_use_refprop()
          assert previous_backend != pygaps.COOLPROP_BACKEND
          pygaps.backend_use_coolprop()
          assert previous_backend == pygaps.COOLPROP_BACKEND
  
      def test_backend_names_coolprop(self):
          """Test if CoolProp can be called for database adsorbents."""
          for adsorbate in pygaps.ADSORBATE_LIST:
              try:
                  adsorbate.backend.molar_mass()
              except pygaps.utilities.exceptions.ParameterError:
                  pass
  
      def test_backend_names_refprop(self):
          """Test if RERFPROP can be called for database adsorbents."""
          version = CoolProp.CoolProp.get_global_param_string("REFPROP_version")
          if version == 'n/a':
              pass
          else:
              pygaps.backend_use_refprop()
              for adsorbate in pygaps.ADSORBATE_LIST:
                  try:
                      adsorbate.backend.molar_mass()
                  except pygaps.utilities.exceptions.ParameterError:
                      pass
              pygaps.backend_use_coolprop()
  
subject: check for refprop