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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 pause(self, historics_id, reason=""):
 """ Pause an existing Historics query. Uses API documented at http://dev.datasift.com/docs/api/rest-api/endpoints/historicspause :param historics_id: id of the job to pause :type historics_id: str :param reason: optional reason for pausing it :type reason: str :return: dict of REST API output with headers attached :rtype: :class:`~datasift.request.DictResponse` :raises: :class:`~datasift.exceptions.DataSiftApiException`, :class:`requests.exceptions.HTTPError` """

        params = {"id": historics_id}
        if reason != "":
            params["reason"] = reason
        return self.request.post('pause', data=params)