Question: what port is associated with the dns service
[{'answer': '53', 'provenance': [{'wikipedia_id': '347136', 'title': 'List of TCP and UDP port numbers', 'start_paragraph_id': 9, 'start_character': 18, 'end_paragraph_id': 9, 'end_character': 20, 'bleu_score': 1.0, 'section': 'Section::::Dynamic, private or ephemeral ports.\n'}]}]