docstr: Returns information about the subrepo the key is part of.
code: def _get_subrepo_info(
      self, key: Key
  ) -> Tuple["Repo", Optional[DataFileSystem], Key]:
      """
      Returns information about the subrepo the key is part of.
      """
      repo = self._get_repo(key)
      repo_key: Key
      if repo is self.repo:
          repo_key = ()
          subkey = key
      else:
          repo_key = self._get_key(repo.root_dir)
          subkey = key[len(repo_key) :]
  
      dvc_fs = self._datafss.get(repo_key)
      return repo, dvc_fs, subkey
  
imports: import errno
  import functools
  import ntpath
  import os
  import posixpath
  import threading
  from collections import deque
  from contextlib import ExitStack, suppress
  from typing import TYPE_CHECKING, Any, Callable, Dict, Optional, Tuple, Type, Union
  from fsspec.spec import AbstractFileSystem
  from funcy import wrap_with
  from dvc.log import logger
  from dvc_objects.fs.base import FileSystem
  from .data import DataFileSystem
label_desc: Use image node_id 22 for calling the _DVCFileSystem obj's underlying member method code with example usage: obj._get_subrepo_info(key) and returns: repo,  dvc_fs,  subkey