bulatb

  <ul> Players
    <li> Alice
    <li> Bob
    <li> Carol
  </ul>

  <ol> Leaderboard
    <li> Bob
    <li> Alice
    <li> Carol
  </ol>

  active_users = Query(User).filter(active=True)

  def active_users_except(exclude):
      return active_users.filter(User.id.not_in(exclude)

  exclude_criterion = rude_users()  # A subquery expression
  polite_active_users = load_records(
      active_users_except(exclude_criterion)
  )

  @dataclass
  class ActiveUsers(QueryTemplate):
      active_if: Expression = User.active == true()

      @classmethod
      excluding(cls, bad_set):
          return cls(
              and_(
                  User.active == true(),
                  User.id.not_in(bad_set)
              )
          )

      @property
      def query(self):
          return Query(User).filter(self.active_if)

  load_records(
      ActiveUsers.excluding(select_alice | select_bob).query
  )