implement dm.from_dfs

    def set_detectors(self, detectors=None):

        raise DeprecationWarning("This method is deprecated, please directly use dm.target_detectors = detectors!")

    @staticmethod

    def from_dfs(expid, ver_sim="C5.2", datatype="mbi", dir_l1="."):

        raise NotImplementedError("from_dfs is currently not available!")

    @staticmethod

    def from_dir(ver_sim="C5.2", datatype="mbi", dir_l0=".", dir_l1=".", path_aux="", dfs_mode=False, dfs_node="kmust"):

        """ initialize the multi-band imaging data manager """

        """ Push SLS spectra to DFS. """

        pass

    @staticmethod

    def from_dfs(obs_id="100000100", datatype="mbi", dir_l0="/L1Pipeline/L0", dir_l1=".",

                 dfs_mode=True, dfs_node="pml"):

        """ Initialize CsstMsDataManager from DFS. """

        records = Level0DataApi().find(obs_id=obs_id)  # query DFS

        tbl = Table([_.__dict__ for _ in records["data"]])

        tbl.sort(["detector_no", "obs_type"])

        if os.uname()[1] == "ubuntu":  # use pml test node

            dfs_root = "/share/dfs"

        else:                          # in docker

            dfs_root = "/dfsroot"

        # (clear and) make directories

        if os.path.exists(dir_l0):

            os.system(f"rm -rf {dir_l0}")

        if os.path.exists(dir_l1):

            os.system(f"rm -rf {dir_l1}")

        os.mkdir(dir_l0)

        os.mkdir(dir_l1)

        for i_rec in range(len(tbl)):  # make symbolic links

            os.symlink(

                src=os.path.join(dfs_root, tbl["file_path"][i_rec]),

                dst=os.path.join(dir_l0, tbl["file_path"][i_rec])

            )

        if datatype == "mbi":

            path_aux = "/share/L1Pipeline/aux/C5.2_ref_mbi/MSC_{}_*_{:02d}_combine.fits"

        elif datatype == "sls":

            path_aux = "/share/L1Pipeline/aux/C5.2_ref_sls/csst_{:02d}{}.fits"

        else:

            path_aux = ""

        # initialize dm

        dm = CsstMsDataManager.from_dir(

            ver_sim="C5.2", datatype=datatype, dir_l0=dir_l0, dir_l1=dir_l1,

            path_aux=path_aux, dfs_mode=dfs_mode, dfs_node=dfs_node

        )

        return dm

    def dfs_l0_query(self, obs_id: str = "100000100"):

        """ Query L0 data from DFS. """

        result = self.dfs_L0DataApi.find(obs_id=str(obs_id))