code: def dump(self, conf_file=None):
          
  
          if conf_file:
              conf_dir = os.path.dirname(conf_file)
              if not conf_dir:
                  conf_dir = self.__invoke_dir
              elif not os.path.exists(conf_dir):
                  os.makedirs(conf_dir)
          else:
              conf_dir = self.__conf_dir
  
          final_conf = {}
          for key, value in list(self.__config.items()):
              if key in self.__cli:
                  continue
              final_conf[key] = value
  
          for key, value in list(self.__cli.items()):
              if key.endswith('index') or key in ['sitemap', 'output']:
                  path = self.__abspath(value, from_conf=False)
                  if path:
                      relpath = os.path.relpath(path, conf_dir)
                      final_conf[key] = relpath
              elif key.endswith('sources') or key.endswith('source_filters'):
                  new_list = []
                  for path in value:
                      path = self.__abspath(path, from_conf=False)
                      if path:
                          relpath = os.path.relpath(path, conf_dir)
                          new_list.append(relpath)
                  final_conf[key] = new_list
              elif key not in ['command', 'output_conf_file']:
                  final_conf[key] = value
  
          with open(conf_file or self.conf_file or 'hotdoc.json', 'w') as _:
              _.write(json.dumps(final_conf, sort_keys=True, indent=4))
docs: Dump the possibly updated config to a file.
  
          Args:
              conf_file: str, the destination, or None to overwrite the
                  existing configuration.