code: def get_next(self, session):
          '''return the name of the next experiment, depending on the user's
             choice to randomize. We don't remove any experiments here, that is
             done on finish, in the case the user doesn't submit data (and
             thus finish). A return of None means the user has completed the
             battery of experiments.
          '''
          next = None
          experiments = session.get('experiments', [])
          if len(experiments) > 0:    
              if app.randomize is True:
                  next = random.choice(range(0,len(experiments)))
                  next = experiments[next]
              else:
                  next = experiments[0]
          return nexf get_next(self, session):
          '''return the name of the next experiment, depending on the user's
             choice to randomize. We don't remove any experiments here, that is
             done on finish, in the case the user doesn't submit data (and
             thus finish). A return of None means the user has completed the
             battery of experiments.
          '''
          next = None
          experiments = session.get('experiments', [])
          if len(experiments) > 0:    
              if app.randomize is True:
                  next = random.choice(range(0,len(experiments)))
                  next = experiments[next]
              else:
                  next = experiments[0]
          return next
docs: return the name of the next experiment, depending on the user's
             choice to randomize. We don't remove any experiments here, that is
             done on finish, in the case the user doesn't submit data (and
             thus finish). A return of None means the user has completed the
             battery of experiments.