Question: who plays the mom in mamma mia 2
[{'answer': 'Meryl Streep', 'provenance': [{'wikipedia_id': '54535911', 'title': 'Mamma Mia! Here We Go Again', 'start_paragraph_id': 1, 'start_character': 583, 'end_paragraph_id': 1, 'end_character': 595, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]