Question: how many episodes are in season 4 of agents of shield
[{'answer': '22', 'provenance': [{'wikipedia_id': '49635999', 'title': 'Agents of S.H.I.E.L.D. (season 4)', 'start_paragraph_id': 3, 'start_character': 98, 'end_paragraph_id': 3, 'end_character': 100, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}]