Question: who invaded wirrawee in tomorrow when the war began
[{'answer': 'never specified in the books', 'provenance': [{'wikipedia_id': '3203702', 'title': 'Tomorrow series', 'start_paragraph_id': 3, 'start_character': 23, 'end_paragraph_id': 3, 'end_character': 51, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '3203702', 'title': 'Tomorrow series', 'start_paragraph_id': 3, 'start_character': 0, 'end_paragraph_id': 3, 'end_character': 694, 'bleu_score': 0.621145400691659, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 4208737724752047147}, 'section': 'Section::::Abstract.'}]}]