code: def _set_opt(config_dict, path, value):
      
      if value is None:
          return
  
      if '.' not in path:
          config_dict[path] = value
          return
  
      key, rest = path.split(".", 1)
      if key not in config_dict:
          config_dict[key] = {}
  
      _set_opt(config_dict[key], rest, value)
docs: Set the value in the dictionary at the given path if the value is not None.