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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 usage(self, period=None, start=None, end=None):
 """ Get account usage information :param period: Period is one of either hourly, daily or monthly :type period: str :param start: Determines time period of the usage :type start: int :param end: Determines time period of the usage :type end: int :return: dict of REST API output with headers attached :rtype: :class:`~datasift.request.DictResponse` :raises: :class:`~datasift.exceptions.DataSiftApiException`, :class:`requests.exceptions.HTTPError` """


        params = {}

        if period:
            params['period'] = period
        if start:
            params['start'] = start
        if end:
            params['end'] = end

        return self.request.get('usage', params)