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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 tournament_number2name(self, number):
 """Translate tournament number to tournament name. Args: number (int):
 tournament number to translate Returns: name (str):
 name of the tournament or `None` if unknown. Examples: 'delta' None """

        tournaments = self.get_tournaments()
        d = {t['tournament']: t['name'] for t in tournaments}
        return d.get(number, None)