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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 filter(self, id):
 """ Fetches information about the filter with the specified `id`. Returns a `filter dict`_. """

        id = self.__unpack_id(id)
        url = '/api/v1/filters/{0}'.format(str(id))
        return self.__api_request('GET', url)