Question: according to jean piaget what is the stage of cognitive development at infancy
[{'answer': 'sensorimotor stage', 'provenance': [{'wikipedia_id': '1058599', 'title': "Piaget's theory of cognitive development", 'start_paragraph_id': 13, 'start_character': 110, 'end_paragraph_id': 13, 'end_character': 128, 'bleu_score': 1.0, 'section': 'Section::::Nature of intelligence: operative and figurative.:Sensorimotor stage.\n'}]}, {'provenance': [{'wikipedia_id': '1058599', 'title': "Piaget's theory of cognitive development", 'start_paragraph_id': 13, 'start_character': 0, 'end_paragraph_id': 13, 'end_character': 618, 'bleu_score': 0.80545354099132, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 9746812652615056747}, 'section': 'Section::::Nature of intelligence: operative and figurative.:Sensorimotor stage.\n'}]}]