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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def unique_event_labels(event_list):
 """Find the unique event labels Parameters event_list : list or dcase_util.containers.MetaDataContainer A list containing event dicts Returns ------- list Unique labels in alphabetical order """


    if isinstance(event_list, dcase_util.containers.MetaDataContainer):
        return event_list.unique_event_labels

    else:
        labels = []
        for event in event_list:
            if 'event_label' in event and event['event_label'] not in labels:
                labels.append(event['event_label'])

        labels.sort()
        return labels