code: def add(self, entry):
          
          # Empty or None values for organizations are not allowed
          if not entry:
              return CMD_SUCCESS
  
          try:
              api.add_to_matching_blacklist(self.db, entry)
          except InvalidValueError as e:
              # If the code reaches here, something really wrong has happened
              # because entry cannot be None or empty
              raise RuntimeError(str(e))
          except AlreadyExistsError as e:
              msg = "%s already exists in the registry" % entry
              self.error(msg)
              return e.code
  
          return CMD_SUCCESS
docs: Add entries to the blacklist.
  
          This method adds the given 'entry' to the blacklist.
  
          :param entry: entry to add to the blacklist