code: def copy_extras(config):
    
    outdir = config['outdir']
    for dst, src in config['extras'].items():
      dst_path = os.path.join(outdir, dst)
      dst_dir = os.path.dirname(dst_path)
      if not os.path.isdir(dst_dir):
        os.makedirs(dst_dir)
      shutil.copy(src, dst_path)
docs: copy over "extra" files named in config json: stylesheets, logos, ...