Question: who sang at the opening ceremony of the 2018 commonwealth games
[{'answer': 'Delta Goodrem', 'provenance': [{'wikipedia_id': '56887321', 'title': '2018 Commonwealth Games opening ceremony', 'start_paragraph_id': 2, 'start_character': 515, 'end_paragraph_id': 2, 'end_character': 528, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]