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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 start(self, hash, name=None, service='facebook'):
 """ Start a recording for the provided hash :param hash: The hash to start recording with :type hash: str :param name: The name of the recording :type name: str :param service: The service for this API call (facebook, etc) :type service: 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 = {'hash': hash}

        if name:
            params['name'] = name

        return self.request.post(service + '/start', params)