Which candidates are from the Missouri 3 district?
{'header': ['District', 'Incumbent', 'Party', 'First elected', 'Result', 'Candidates'], 'page_title': 'United States House of Representatives elections, 1986', 'section_title': '', 'caption': '', 'rows': [['Missouri 1', 'Bill Clay', 'Democratic', '1968', 'Re-elected', 'Bill Clay (D) 66.1% Robert J. Wittman (R) 33.9%'], ['Missouri 2', 'Robert A. Young', 'Democratic', '1976', 'Lost re-election Republican gain', 'Jack Buechner (R) 51.9% Robert A. Young (D) 48.1%'], ['Missouri 3', 'Dick Gephardt', 'Democratic', '1976', 'Re-elected', 'Dick Gephardt (D) 69.0% Roy Amelung (R) 31.0%'], ['Missouri 4', 'Ike Skelton', 'Democratic', '1976', 'Re-elected', 'Ike Skelton (D) Unopposed'], ['Missouri 7', 'Gene Taylor', 'Republican', '1972', 'Re-elected', 'Gene Taylor (R) 67.0% Ken Young (D) 33.0%']]}