code: def validate_one_format(jupytext_format):
      """Validate extension and options for the given format"""
      if not isinstance(jupytext_format, dict):
          raise JupytextFormatError(
              "Jupytext format should be a dictionary"
          )
  
      if (
          "format_name" in jupytext_format
          and jupytext_format["format_name"] not in _VALID_FORMAT_NAMES
      ):
          raise JupytextFormatError(
              "{} is not a valid format name. Please choose one of {}".format(
                  jupytext_format.get("format_name"),
                  ", ".join(_VALID_FORMAT_NAMES),
              )
          )
  
      for key in jupytext_format:
          if key not in _VALID_FORMAT_INFO + _VALID_FORMAT_OPTIONS:
              raise JupytextFormatError(
                  "Unknown format option '{}' - should be one of '{}'".format(
                      key, "', '".join(_VALID_FORMAT_OPTIONS)
                  )
              )
          value = jupytext_format[key]
          if key in _BINARY_FORMAT_OPTIONS:
              if not isinstance(value, bool):
                  raise JupytextFormatError(
                      "Format option '{}' should be a bool, not '{}'".format(
                          key, str(value)
                      )
                  )
  
      if "extension" not in jupytext_format:
          raise JupytextFormatError("Missing format extension")
      ext = jupytext_format["extension"]
      if ext not in NOTEBOOK_EXTENSIONS + [".auto"]:
          raise JupytextFormatError(
              "Extension '{}' is not a notebook extension. Please use one of '{}'.".format(
                  ext, "', '".join(NOTEBOOK_EXTENSIONS + [".auto"])
              )
          )
  
      return jupytext_format
  
imports: import os
  import re
  import warnings
  import nbformat
  import yaml
  from .cell_reader import DoublePercentScriptCellReader, HydrogenCellReader, LightScriptCellReader, MarkdownCellReader, RMarkdownCellReader, RScriptCellReader, SphinxGalleryScriptCellReader
  from .cell_to_text import BareScriptCellExporter, DoublePercentCellExporter, HydrogenCellExporter, LightScriptCellExporter, MarkdownCellExporter, RMarkdownCellExporter, RScriptCellExporter, SphinxGalleryCellExporter
  from .header import header_to_metadata_and_cell, insert_or_test_version_number
  from .languages import _COMMENT_CHARS, _SCRIPT_EXTENSIONS, same_language
  from .magics import is_magic
  from .metadata_filter import metadata_filter_as_string
  from .myst import MYST_FORMAT_NAME, is_myst_available, matches_mystnb, myst_extensions, myst_version
  from .pandoc import is_pandoc_available, pandoc_version
  from .stringparser import StringParser
  from .version import __version__
label_desc: Use image node_id 15 for calling a global function with example usage: validate_one_format(jupytext_format) and returns: jupytext_format