public function removeBets() {
    $query = \Drupal::entityQuery('bet');
    $query->condition('game', $this->id());
    $ids = $query->execute();
    $bets = Bet::loadMultiple($ids);
    foreach ($bets as $bet) {
      $bet->delete();
    }
    \Drupal::logger('mespronos')->notice(t('Bets removed on game #@id (@game_label) : @nb_bets removed', [
      '@id' => $this->id(),
      '@game_label' => $this->label(),
      '@nb_bets' => \count($ids),
    ]));
    return \count($ids);
  }