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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='hour'):
 """ Check the number of objects processed and delivered for a given time period Uses API documented at http://dev.datasift.com/docs/api/rest-api/endpoints/usage :param period: (optional) time period to measure usage for, can be one of "day", "hour" or "current" (5 minutes), default is hour :type period: str :returns: dict with extra response data :rtype: :class:`~datasift.request.DictResponse` :raises: :class:`~datasift.exceptions.DataSiftApiException`, :class:`requests.exceptions.HTTPError` """

        return self.request.get('usage', params=dict(period=period))