class_docstr: Template class to implement header protocol
code: def from_fileobj(klass: type[HdrT], fileobj: io.IOBase) -> HdrT:
      raise NotImplementedError
  
imports: from __future__ import annotations
  import io
  import typing
  from copy import deepcopy
  from urllib import request
  from ._compression import COMPRESSION_ERRORS
  from .fileholders import FileHolder, FileMap
  from .filename_parser import TypesFilenamesError, _stringify_path, splitext_addext, types_filenames
  from .openers import ImageOpener
label_desc: Use image node_id 2 for calling the FileBasedHeader obj's underlying member method code with example usage: obj.from_fileobj(klass, fileobj) without return types