old_contents: import os
  from dallinger import db
  
  
  class TestBartlett1932(object):
      """Tests for the Bartlett1932 demo class"""
  
      def _make_one(self):
          from demos.bartlett1932.experiment import Bartlett1932
          return Bartlett1932(self._db)
  
      def setup(self):
          self._db = db.init_db(drop_all=True)
          # This is only needed for config, which loads on import
          os.chdir('demos/bartlett1932')
  
      def teardown(self):
          self._db.rollback()
          self._db.close()
          os.chdir('../..')
  
      def test_instantiation(self):
          demo = self._make_one()
          assert demo is not None
  
      def test_networks_holds_single_experiment_node(self):
          demo = self._make_one()
          assert len(demo.networks()) == 1
          assert u'experiment' == demo.networks()[0].role
  
  
  class TestEntryPointImport(object):
  
      def test_bartlett1932_entry_point(self):
          from demos.bartlett1932.experiment import Bartlett1932 as OrigExp
          from dallinger.experiments import Bartlett1932
  
          assert Bartlett1932 is OrigExp
  
new_contents: import os
  import subprocess
  
  from dallinger import db
  
  
  class TestDemos(object):
      """Verify all the built-in demos."""
  
      def test_verify_all_demos(self):
          demo_paths = os.listdir("demos")
          for demo_path in demo_paths:
              if os.path.isdir(demo_path):
                  os.chdir(demo_path)
                  assert subprocess.check_call(["dallinger", "verify"])
                  os.chdir("..")
  
  
  class TestBartlett1932(object):
      """Tests for the Bartlett1932 demo class"""
  
      def _make_one(self):
          from demos.bartlett1932.experiment import Bartlett1932
          return Bartlett1932(self._db)
  
      def setup(self):
          self._db = db.init_db(drop_all=True)
          # This is only needed for config, which loads on import
          os.chdir(os.path.join("demos", "bartlett1932"))
  
      def teardown(self):
          self._db.rollback()
          self._db.close()
          os.chdir(os.path.join("..", ".."))
  
      def test_instantiation(self):
          demo = self._make_one()
          assert demo is not None
  
      def test_networks_holds_single_experiment_node(self):
          demo = self._make_one()
          assert len(demo.networks()) == 1
          assert u'experiment' == demo.networks()[0].role
  
  
  class TestEntryPointImport(object):
  
      def test_bartlett1932_entry_point(self):
          from demos.bartlett1932.experiment import Bartlett1932 as OrigExp
          from dallinger.experiments import Bartlett1932
  
          assert Bartlett1932 is OrigExp
  
subject: Test by verifying all demos