Question: What party was the person who broke Barbara Anne Castle's record as the longest-serving female MP in the House of Commons?
Related documents: [0]  [DOC] Gwyneth Patricia Dunwoody (née Phillips; 12 December 1930 – 17 April 2008) was a British moderate Labour Party politician, who was the Member of Parliament (MP) for Exeter from 1966 to 1970, and then for Crewe (later Crewe and Nantwich) from 1974 to her death in 2008. She had a reputation as a fiercely independent parliamentarian, described as "intelligent, obstinate, opinionated and hard-working". [END] 
[1]  [DOC] Barbara Anne Castle, Baroness Castle of Blackburn, PC, GCOT (née Betts, 6 October 1910 – 3 May 2002) was a British Labour Party politician who was the Member of Parliament for Blackburn from 1945 to 1979, making her the longest-serving female MP in the history of the House of Commons, until that record was broken in 2007 by Gwyneth Dunwoody. She later became the Member of the European Parliament for Greater Manchester from 1979 to 1989. One of the most significant Labour Party politicians of the 20th century, she served in the Cabinet under Prime Minister Harold Wilson in a number of roles, including as Secretary of State for Employment, Secretary of State for Health and Social Services, and First Secretary of State. [END] 
Answer: 
Labour Party
Labour Party