Create a cluster of BIG-IP® devices.

        :param kwargs: dict -- keyword arguments for cluster manager

def create(self, **kwargs):
        '''Create a cluster of BIG-IP® devices.

        :param kwargs: dict -- keyword arguments for cluster manager
        '''

        try:
            cluster = getattr(self, "cluster", None)
        except NoClusterToManage:
            cluster = None
        if cluster is not None:
            msg = 'The ClusterManager is already managing a cluster.'
            raise AlreadyManagingCluster(msg)

        self._check_device_number(kwargs['devices'])
        self.trust_domain.create(
            devices=kwargs['devices'],
            partition=kwargs['device_group_partition']
        )
        self.device_group.create(**kwargs)
        self.cluster = Cluster(**kwargs)