Resets an attribute of a snapshot to its default value.

        :type snapshot_id: string
        :param snapshot_id: ID of the snapshot

        :type attribute: string
        :param attribute: The attribute to reset

        :rtype: bool
        :return: Whether the operation succeeded or not

def reset_snapshot_attribute(self, snapshot_id,
                                 attribute='createVolumePermission'):
        """
        Resets an attribute of a snapshot to its default value.

        :type snapshot_id: string
        :param snapshot_id: ID of the snapshot

        :type attribute: string
        :param attribute: The attribute to reset

        :rtype: bool
        :return: Whether the operation succeeded or not
        """
        params = {'SnapshotId' : snapshot_id,
                  'Attribute' : attribute}
        return self.get_status('ResetSnapshotAttribute', params, verb='POST')