What series was sorted at number 3?
{'header': ['#', 'Series Sorted', 'Title', 'Author', 'Doctor', 'Featuring', 'Released'], 'page_title': 'List of Doctor Who audio plays by Big Finish', 'page_id': '', 'types': ['real', 'text', 'text', 'text', 'text', 'text', 'text'], 'id': '1-1620397-5', 'section_title': 'Series 3', 'caption': 'Series 3', 'rows': [['1', '6EB/A', 'The Elite', 'Barbara Clegg and John Dorney', '5th', 'Tegan , Nyssa , Dalek', 'October 2011'], ['2', '6EB/B', 'Hexagora', 'Peter Ling & Hazel Adair and Paul Finch', '5th', 'Tegan, Nyssa', 'November 2011'], ['3', '6EB/C', 'The Children of Seth', 'Christopher Bailey and Marc Platt', '5th', 'Tegan, Nyssa', 'December 2011'], ['5', '6Y/AJ', 'Power Play', 'Gary Hopkins Category:Articles with hCards', '6th', 'Peri, Victoria', 'June 2012'], ['6', '6Y/AK', 'The First Sontarans', 'Andrew Smith', '6th', 'Peri, Sontarans , Rutans', 'July 2012'], ['7', 'H/C', 'The Masters of Luxor', 'Anthony Coburn (adapted by Nigel Robinson)', '1st', 'Susan Foreman, Ian Chesterton, Barbara Wright', 'August 2012']], 'name': 'table_1620397_5'}