code: def _get_local_folder(self, root=None):
          
          if root is None:
              root = Path()
          for folders in ['.'], [self.user, self.napp]:
              kytos_json = root / Path(*folders) / 'kytos.json'
              if kytos_json.exists():
                  with kytos_json.open() as file_descriptor:
                      meta = json.load(file_descriptor)
                      # WARNING: This will change in future versions, when
                      # 'author' will be removed.
                      username = meta.get('username', meta.get('author'))
                      if username == self.user and meta.get('name') == self.napp:
                          return kytos_json.parent
          raise FileNotFoundError('kytos.json not found.')
docs: Return local NApp root folder.
  
          Search for kytos.json in _./_ folder and _./user/napp_.
  
          Args:
              root (pathlib.Path): Where to begin searching.
  
          Return:
              pathlib.Path: NApp root folder.
  
          Raises:
              FileNotFoundError: If there is no such local NApp.