'Attaches a single server to a shared storage
:param storage_id: Id of the shared storage
:param server_id: Id of the server to be attached to the shared storage
:param rights:
:return:
:rtype: \'dict\''

def ex_attach_server_to_shared_storage(self, storage_id, server_id, rights):

    body = {'severs': [{'id': server_id, 'rights': rights}]}
    response = self.connection.request(action=('shared_storages/%s/servers' % storage_id), data=body, method='POST')
    return response.object
