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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 get_crime_category(self, id, date=None):
 """ Get a particular crime category by ID, valid at a particular date. Uses the crime-categories_ API call. :rtype: CrimeCategory :param str id: The ID of the crime category to get. :param date: The date that the given crime category is valid for (the latest date is used if ``None``). :type date: str or None :return: A crime category with the given ID which is valid for the specified date (or at the latest date, if ``None``). """


        try:
            return self._get_crime_categories(date=date)[id]
        except KeyError:
            raise InvalidCategoryException(
                'Category %s not found for %s' % (id, date))