def add_documents(self, documents: Union[List[str], "Dataset"], column: Optional[str] = None):
        """
        Add documents to the index.
        If the documents are inside a certain column, you can specify it using the `column` argument.
        """
        index_name = self.es_index_name
        index_config = self.es_index_config
        self.es_client.indices.create(index=index_name, body=index_config)
        number_of_docs = len(documents)
        progress = hf_tqdm(unit="docs", total=number_of_docs)
        successes = 0

        def passage_generator():
            if column is not None:
                for i, example in enumerate(documents):
                    yield {"text": example[column], "_id": i}
            else:
                for i, example in enumerate(documents):
                    yield {"text": example, "_id": i}

        # create the ES index
        import elasticsearch as es