def METHOD_NAME(self, document_id: str) -> str:
    """Load a document from Google Docs.
    Args:
        document_id: the document id.
    Returns:
        The document text.
    """
    import googleapiclient.discovery as discovery
    credentials = self._get_credentials()
    docs_service = discovery.build("docs", "v1", credentials=credentials)
    doc = docs_service.documents().get(documentId=document_id).execute()
    doc_content = doc.get("body").get("content")
    return self._read_structural_elements(doc_content)