Question: what are the main imports of sri lanka
[{'answer': 'petroleum', 'provenance': [{'wikipedia_id': '27415', 'title': 'Economy of Sri Lanka', 'start_paragraph_id': 13, 'start_character': 22, 'end_paragraph_id': 13, 'end_character': 31, 'bleu_score': 1.0, 'section': 'Section::::Economic history.\n'}]}, {'answer': 'machinery and transportation equipment'}, {'answer': 'textile fabrics'}, {'answer': 'building materials'}, {'answer': 'mineral products'}, {'answer': 'foodstuffs'}]