Question: where did painters perfect the technique of painting with an oil medium
[{'answer': 'Netherlandish painting', 'provenance': [{'wikipedia_id': '22605', 'title': 'Oil painting', 'start_paragraph_id': 2, 'start_character': 414, 'end_paragraph_id': 2, 'end_character': 436, 'bleu_score': 1.0, 'section': 'Section::::Abstract.'}]}, {'provenance': [{'wikipedia_id': '22605', 'title': 'Oil painting', 'start_paragraph_id': 9, 'start_character': 0, 'end_paragraph_id': 9, 'end_character': 818, 'bleu_score': 0.9050149391192781, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 14644771278875181432}, 'section': 'Section::::History.\n'}]}]