def extract_gt_tokens(text):
    """
    Given GT string, method to extract GT labels.
    GT string should be formatted as Twitter-Event-Data-2019.

    parameters
    -----------
    :param text: str
    :return: list
        List of GT labels corresponding to a single event
        Since there can be duplicate definitions for a single event, this list contains separate label lists for each
        duplicate definition.
    """
    duplicates = []

    for element in text.split("|"):
        labels = []
        for subelement in element.split("["):
            if subelement:
                subelement = subelement.replace("\n", "")
                subelement = subelement.replace("]", "")
                tokens = subelement.split(",")
                labels.append(tokens)
        duplicates.append(labels)
    return duplicates