Question: where is iron absorbed in the digestive system
[{'answer': 'in the duodenum', 'provenance': [{'wikipedia_id': '3335116', 'title': 'Human iron metabolism', 'start_paragraph_id': 26, 'start_character': 109, 'end_paragraph_id': 26, 'end_character': 124, 'bleu_score': 1.0, 'section': 'Section::::Mechanisms of iron regulation.:Systemic iron regulation.:Dietary iron uptake.\n'}]}, {'provenance': [{'wikipedia_id': '3335116', 'title': 'Human iron metabolism', 'start_paragraph_id': 26, 'start_character': 0, 'end_paragraph_id': 26, 'end_character': 684, 'bleu_score': 0.9825310706027971, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17968498998068706715}, 'section': 'Section::::Mechanisms of iron regulation.:Systemic iron regulation.:Dietary iron uptake.\n'}]}]