Question: The South Shield by-election in 2013 was triggered by the resignation of which British Labour Party politician? 

full_context: Document 1: Marion Kozak: Marion Kozak or Marion Kozak Miliband (born 1934 as Dobra Jenta Kozak, also known as Maria Kozak) is a Polish-born British activist. She emigrated to the United Kingdom in the 1950s. In 1961 she married Ralph Miliband (1924–1994) and their two sons, David Miliband and Ed Miliband, have risen to prominence in modern-day British politics.
Document 2: Liberal Democrats leadership election, 2007: The 2007 Liberal Democrats leadership election was held following the resignation of Sir Menzies Campbell as leader on 15 October 2007, after 19 months as leader of the Liberal Democrats, the third-largest political party in the United Kingdom. Vincent Cable, the deputy leader of the parliamentary party, was acting leader until the conclusion of the leadership election. The result was announced on 18 December 2007 with Nick Clegg winning by a narrow margin of 1.2%.
Document 3: Ed Miliband: Edward Samuel Miliband (born 24 December 1969) is a British politician who was Leader of the Labour Party as well as Leader of the Opposition between 2010 and 2015. He became the Member of Parliament (MP) for Doncaster North in 2005, being re-elected in 2010, 2015, and 2017, and served in the Cabinet from 2007-10 under Prime Minister Gordon Brown.
Document 4: Liberal Democrats leadership election, 2006: In the 2006 Liberal Democrats leadership election, Sir Menzies Campbell was elected to succeed Charles Kennedy as Leader of the Liberal Democrats, the third-largest political party in the United Kingdom.
Document 5: David Cameron: David William Donald Cameron ( ; born 9 October 1966) is a British politician who was Prime Minister of the United Kingdom from 2010 to 2016 and Leader of the Conservative Party from 2005 to 2016. He was Member of Parliament (MP) for Witney from 2001 to 2016. Cameron identifies as a One-Nation Conservative, and has been associated with both economically liberal and socially liberal policies.
Document 6: David Davis (British politician): David Michael Davis (born 23 December 1948) is a British Conservative Party politician who has been the Secretary of State for Exiting the European Union since 2016 and the Member of Parliament (MP) for Haltemprice and Howden since 1997, having previously been the MP for Boothferry from 1987. Davis was sworn of the Privy Council in the 1997 New Year Honours, having previously been Minister of State for Europe from 1994 to 1997.
Document 7: Labour Party (UK) Shadow Cabinet election, 1995: Elections to the Labour Party's Shadow Cabinet took place in October 1995, at the beginning of the 1995/6 session of parliament. Under the rules then in effect, the Commons members of the Parliamentary Labour Party elected 19 members of the Official Opposition Shadow Cabinet, who were then assigned portfolios by the leader. The Labour peers elected the Leader of the Opposition in the House of Lords. In addition, the Leader of the Labour Party and Deputy Leader (Tony Blair and John Prescott, respectively) were members by virtue of those offices. With this election, for the first time, the role Opposition Chief Whip was simply another portfolio to be handed out rather than an office separately elected by the PLP. The 19 elected members of the Shadow Cabinet were the ones with the largest number of votes. MPs were required to vote for at least four women, but women were not necessarily guaranteed places in the Shadow Cabinet.
Document 8: David Miliband: David Wright Miliband (born 15 July 1965) is a British Labour Party politician, charity chief executive and public policy analyst who was the Secretary of State for Foreign and Commonwealth Affairs from 2007 to 2010 and the Member of Parliament (MP) for South Shields from 2001 to 2013. He and his brother, Ed Miliband, were the first siblings to sit in the Cabinet simultaneously since Edward, Lord Stanley, and Oliver Stanley in 1938.
Document 9: Tony Blair: Anthony Charles Lynton Blair (born 6 May 1953) is a British politician who served as Prime Minister of the United Kingdom from 2 May 1997 to 27 June 2007 and Leader of the Labour Party from 21 July 1994 to 24 June 2007. He previously served as Leader of the Opposition from 21 July 1994 to 2 May 1997. He is the most recent British Labour Party leader to have won a general election.
Document 10: Labour Party (UK) Shadow Cabinet election, 1993: Elections to the Labour Party's Shadow Cabinet took place in October 1993, at the beginning of the 1993/4 session of parliament. Under the rules then in effect, the Commons members of the Parliamentary Labour Party elected 18 members of the Official Opposition Shadow Cabinet, who were then assigned portfolios by the leader. The Commons members of the PLP separately elected the Chief Whip, and the Labour peers elected the Leader of the Opposition in the House of Lords. In addition, the Leader of the Labour Party and Deputy Leader (John Smith and Margaret Beckett, respectively) were members by virtue of those offices. The 18 elected members of the Shadow Cabinet were the ones with the largest number of votes. Beginning with this election, MPs were required to vote for at least four women, but women were no longer guaranteed three places in the Shadow Cabinet.
Document 11: Damian Green: Damian Howard Green (born 17 January 1956) is a British politician who has been the Conservative Member of Parliament for Ashford since 1997 and the First Secretary of State and Minister for the Cabinet Office since 11 June 2017. Green was born in Barry, Wales, and studied PPE at Balliol College, Oxford. Before entering politics, Green worked as a journalist for the BBC, Channel 4 and "The Times".
Document 12: Wayne David: Wayne David (born 1 July 1957) is a British Labour Party politician, who has been the Member of Parliament (MP) for Caerphilly since 2001. He was Parliamentary Under-Secretary of State at the Wales Office from 2008 to 2010. He was appointed Shadow Europe Minister in 2010, Shadow Minister for Political and Constitutional Reform in 2011 and as Ed Miliband's Parliamentary Private Secretary in October 2013.
Document 13: Hilary Benn: Hilary James Wedgwood Benn (born 26 November 1953) is a British Labour Party politician who has been the Member of Parliament (MP) for Leeds Central since the by-election in 1999. He served in the cabinet from 2003–10, under the premierships of both Tony Blair and Gordon Brown. From 2010–16, he served in various Labour Party shadow cabinets, most recently as Shadow Foreign Secretary from May 2015 until June 2016, when he was dismissed by Labour leader Jeremy Corbyn. In October 2016, he was elected as the Chair of the new Exiting the European Union Select Committee.
Document 14: Clare Short: Clare Short (born 15 February 1946) is a British politician, and a member of the Labour Party. She was the Member of Parliament for Birmingham Ladywood from 1983 to 2010; for most of this period she was a Labour Party MP, but she resigned the party whip in 2006 and served the remainder of her term as an Independent. She stood down as a member of parliament at the 2010 general election. Short was Secretary of State for International Development in the government of Prime Minister Tony Blair from 3 May 1997 until her resignation from that post on 12 May 2003. Shortly before her retirement from Parliament in 2010, she was strongly rebuked by her own party when she announced her support for a hung parliament, a situation which subsequently occurred at the 2010 General Election.
Document 15: South Shields by-election, 2013: The South Shields by-election was a by-election held for the United Kingdom House of Commons constituency of South Shields. It was triggered by the resignation of David Miliband, the previous Member of Parliament (MP) and former Shadow Foreign Secretary, who had held the seat for Labour since 2001. The by-election took place on 2 May 2013, coinciding with local elections across England.
ground_truth: David Wright Miliband