def METHOD_NAME():
  """Requests an update of the toolchain to the specific hashes we have at
  this revision. The update outputs a .json of the various configuration
  information required to pass to gyp which we use in |GetToolchainDir()|.
  """
  depot_tools_win_toolchain = \
      bool(int(os.environ.get('DEPOT_TOOLS_WIN_TOOLCHAIN', '1')))
  if sys.platform in ('win32', 'cygwin') and depot_tools_win_toolchain:
    depot_tools_path = FindDepotTools()
    # Necessary so that get_toolchain_if_necessary.py will put the VS toolkit
    # in the correct directory.
    os.environ['GYP_MSVS_VERSION'] = GetVisualStudioVersion()
    get_toolchain_args = [
        sys.executable,
        os.path.join(depot_tools_path,
                    'win_toolchain',
                    'get_toolchain_if_necessary.py'),
        '--output-json', json_data_file,
      ] + _GetDesiredVsToolchainHashes()
    subprocess.check_call(get_toolchain_args)
  return 0