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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 log_game_start(self, players, terrain, numbers, ports):
 """ Begin a game. Erase the log, set the timestamp, set the players, and write the log header. The robber is assumed to start on the desert (or off-board). :param players: iterable of catan.game.Player objects :param terrain: list of 19 catan.board.Terrain objects. :param numbers: list of 19 catan.board.HexNumber objects. :param ports: list of catan.board.Port objects. """

        self.reset()
        self._set_players(players)
        self._logln('{} v{}'.format(__name__, __version__))
        self._logln('timestamp: {0}'.format(self.timestamp_str()))
        self._log_players(players)
        self._log_board_terrain(terrain)
        self._log_board_numbers(numbers)
        self._log_board_ports(ports)
        self._logln('...CATAN!')