in qldb_streaming_sample/app.py [0:0]
def get_data_metdata_from_revision_record(revision_record):
    """
    Retrieves the data block from revision Revision Record
    Parameters:
       topic_arn (string): The topic you want to publish to.
       message (string): The message you want to send.
    """
    revision_data = None
    revision_metadata = None
    if ("payload" in revision_record) and ("revision" in revision_record["payload"]):
        if ("data" in revision_record["payload"]["revision"]):
            revision_data = revision_record["payload"]["revision"]["data"]
        if ("metadata" in revision_record["payload"]["revision"]):
            revision_metadata = revision_record["payload"]["revision"]["metadata"]
    return [revision_data, revision_metadata]