Question: how many countries are there in asian continent
[{'answer': '48', 'provenance': [{'wikipedia_id': '689', 'title': 'Asia', 'start_paragraph_id': 40, 'start_character': 537, 'end_paragraph_id': 40, 'end_character': 539, 'bleu_score': 1.0, 'section': 'Section::::Geography and climate.\n'}]}, {'provenance': [{'wikipedia_id': '689', 'title': 'Asia', 'start_paragraph_id': 40, 'start_character': 0, 'end_paragraph_id': 40, 'end_character': 632, 'bleu_score': 0.9173188845244291, 'meta': {'yes_no_answer': 'NONE', 'annotation_id': 15384236871536438997}, 'section': 'Section::::Geography and climate.\n'}]}]