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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 week(self):
 """ Returns an ``int`` of the week number in the season, such as 1 for the first week of the regular season. """

        if self._week.lower() == 'wild card':
            return WILD_CARD
        if self._week.lower() == 'division':
            return DIVISION
        if self._week.lower() == 'conf. champ.':
            return CONF_CHAMPIONSHIP
        if self._week.lower() == 'superbowl':
            return SUPER_BOWL
        return self._week