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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _num_players(self):
 """Compute number of players, both human and computer."""

        self._player_num = 0
        self._computer_num = 0
        for player in self._header.scenario.game_settings.player_info:
            if player.type == 'human':
                self._player_num += 1
            elif player.type == 'computer':
                self._computer_num += 1