docs: def create_index(self, index):
      """Creates and opens index folder for given index.
      If the index already exists, it just opens it, otherwise it creates it first.
      """
  
      index._path = os.path.join(self.indexes_path, index._name)
  
      if whoosh.index.exists_in(index._path):
        _whoosh = whoosh.index.open_dir(index._path)
      elif not os.path.exists(index._path):
        os.makedirs(index._path)
        _whoosh = whoosh.index.create_in(index._path, index._schema)
      index._whoosh = _whoosh