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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 failover(self, sync=None, force=None):
 """ Fails over a replication session. :param sync: True - sync the source and destination resources before failing over the asynchronous replication session or keep them in sync after failing over the synchronous replication session. False - don't sync. :param force: True - skip pre-checks on file system(s) replication sessions of a NAS server when a replication failover is issued from the source NAS server. False - don't skip pre-checks. """

        req_body = self._cli.make_body(sync=sync, force=force)
        resp = self.action('failover', **req_body)
        resp.raise_if_err()
        return resp