Question: which part of the uterus does implantation occur in
[{'answer': 'the wall of the uterus', 'provenance': [{'wikipedia_id': '7357937', 'title': 'Implantation (human embryo)', 'start_paragraph_id': 1, 'start_character': 81, 'end_paragraph_id': 1, 'end_character': 103, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '7357937', 'title': 'Implantation (human embryo)', 'start_paragraph_id': 1, 'start_character': 0, 'end_paragraph_id': 1, 'end_character': 285, 'bleu_score': 0.9611463610973231, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 17980350268312522330}, 'section': 'Section::::Abstract.'}]}]