concept Topic
  purpose to group related items together

  state
    label: String
    label_count: Integer

  actions
    retrieveTopic()
      pre true
      // Additional logic to retrieve a specific topic based on the label
      set label, label_count from selectTopic()

  operational principle
    after retrieveTopic(), label and label_count are populated with data for the specific topic

  where
    selectTopic(): (String, Integer)
      // Additional logic to execute the SQL query and retrieve data for a specific topic