code: def is_correct(self):
          
          # we are ok at the beginning. Hope we are still ok at the end...
          valid = True
  
          # Better check individual items before displaying the global items list errors and warnings
          for i in self:
              # Alias and display_name hook hook
              # prop_name = getattr(self.__class__, 'name_property', None)
              # if prop_name and not getattr(i, 'alias', '') and hasattr(i, prop_name):
              #     setattr(i, 'alias', getattr(i, prop_name))
              # if prop_name and getattr(i, 'display_name', '') and hasattr(i, prop_name):
              #     setattr(i, 'display_name', getattr(i, prop_name))
  
              # Now other checks
              if not i.is_correct():
                  valid = False
                  i.add_error("Configuration in %s::%s is incorrect; from: %s"
                              % (i.my_type, i.get_name(), i.imported_from))
  
              if i.configuration_errors:
                  self.configuration_errors += i.configuration_errors
              if i.configuration_warnings:
                  self.configuration_warnings += i.configuration_warnings
  
          # Raise all previous warnings
          if self.configuration_warnings:
              for msg in self.configuration_warnings:
                  logger.warning("[items] %s", msg)
  
          # Raise all previous errors
          if self.configuration_errors:
              valid = False
              for msg in self.configuration_errors:
                  logger.error("[items] %s", msg)
  
          return valid
docs: Check if the items list configuration is correct ::
  
          * check if duplicate items exist in the list and warn about this
          * set alias and display_name property for each item in the list if they do not exist
          * check each item in the list
          * log all previous warnings
          * log all previous errors
  
          :return: True if the configuration is correct, otherwise False
          :rtype: bool