Question: Where did David Pitblado work with Winston Churchhill?

full_context: Document 1: Chief Mouser to the Cabinet Office: The Chief Mouser to the Cabinet Office is the title of the official resident cat of the Prime Minister of the United Kingdom at 10 Downing Street. Only four cats, Humphrey, Sybil, Larry and Freya have been given the title officially; other cats were given this title affectionately, usually by the British press. There has been a resident Treasury or Downing Street cat employed as a mouser and pet since the reign of Henry VIII, when Cardinal Wolsey placed his cat by his side while acting in his judicial capacity as Lord Chancellor, an office he assumed in 1515.
Document 2: Great Offices of State: The Great Offices of State in the United Kingdom are the four most senior and prestigious posts in the British government. They are the Prime Minister, Chancellor of the Exchequer, Foreign Secretary and Home Secretary. According to convention, when the Prime Minister names his or her Cabinet, either after a general election or a mid-term reshuffle, the first Cabinet ministers to be announced are the Chancellor, the Foreign Secretary and the Home Secretary.
Document 3: David Pitblado: Sir David Bruce Pitblado KCB CVO (18 August 1912–9 July 1997) was a principal private secretary to the office of the Prime Minister of the United Kingdom. Serving from 1951 to 1956, he was associated with Prime Ministers Clement Attlee, Winston Churchill, and Anthony Eden. With his colleague Jock Colville, he was one of Churchill's last two principal private secretaries at 10 Downing Street.
Document 4: Clement Attlee: Clement Richard Attlee, 1st Earl Attlee, {'1': ", '2': ", '3': ", '4': "} (3 January 1883 – 8 October 1967) was a British Labour politician who served as Prime Minister of the United Kingdom from 1945 to 1951 and Leader of the Labour Party from 1935 to 1955. In 1940, Attlee took Labour into the wartime coalition government and served under Winston Churchill, becoming the first person to hold the office of Deputy Prime Minister of the United Kingdom. He went on to lead the Labour Party to an unexpected landslide victory at the 1945 general election; forming the first Labour majority government, and a mandate to implement its postwar reforms. The 12.0% national swing from the Conservatives to Labour was unprecedented at that time and remains the largest ever achieved by any party at a general election in British electoral history. He was re-elected with a narrow majority at the 1950 general election. In the following year, Attlee called a snap general election, hoping to increase his parliamentary majority. However, he was narrowly defeated by the Conservatives under the leadership of Winston Churchill; despite winning the most votes of any political party in any general election in British political history until the Conservative Party's fourth consecutive victory in 1992. Attlee remains the longest-ever serving Leader of the Labour Party.
Document 5: 11 Downing Street: 11 Downing Street (sometimes referred to as just Number 11) is the official residence of Britain's Chancellor of the Exchequer (who traditionally also has the title of Second Lord of the Treasury). The residence, in Downing Street in London, was built alongside the official residence of the Prime Minister at Number 10 in 1682.
Document 6: 10 Downing Street: 10 Downing Street, colloquially known in the United Kingdom as Number 10, is the headquarters of the Government of the United Kingdom and the official residence and office of the First Lord of the Treasury, a post which, for much of the 18th and 19th centuries and invariably since 1905, has been held by the Prime Minister.
Document 7: List of Prime Ministers of the United Kingdom: The Prime Minister of the United Kingdom is the head of the Government of the United Kingdom, and chairs Cabinet meetings. There is no specific date when the office of Prime Minister first appeared, as the role was not created but rather evolved over a period of time. The term was used in the House of Commons in 1805 and it was certainly in parliamentary use by the 1880s, and in 1905 the post of Prime Minister was officially given recognition in the order of precedence. Modern historians generally consider Sir Robert Walpole, who led the government of Great Britain from 1721 to 1742, as the first Prime Minister. Walpole is also the longest-serving Prime Minister by this definition. However, Sir Henry Campbell-Bannerman was the first Prime Minister and Margaret Thatcher the longest-serving Prime Minister to have been officially referred to as such.
Document 8: Principal Private Secretary to the Prime Minister: The Principal Private Secretary to the Prime Minister is a senior official in the British Civil Service who acts as Principal Private Secretary to the Prime Minister of the United Kingdom. The holder of this office is traditionally the head of the Prime Minister's Office. In the Civil Service, the role is currently graded as a Director-General. To date, no woman has ever occupied the office. In fiction, the character of Bernard Woolley in the television series "Yes, Prime Minister", occupied this post.
Document 9: Prime Minister's Official Spokesperson: The Prime Minister's Official Spokesperson or alternatively Prime Minister's Official Spokesman/Spokeswoman is a position in the United Kingdom's Civil Service, located in the Prime Minister's Office in 10 Downing Street and used by the British Prime Minister to convey information to the public. The Prime Minister's Official Spokesperson usually addresses a small group of press and media correspondents, known as lobby correspondents, each morning to deliver statements on current events on behalf of the Prime Minister.
Document 10: List of residents of 10 Downing Street: Number 10 Downing Street is the residence and office of the First Lord of the Treasury as Prime Minister of the United Kingdom. The headquarters of Her Majesty's Government, it is situated on Downing Street in the City of Westminster in London, England.
Document 11: Timothy Bligh: Sir Timothy James Bligh, KBE, DSO, DSC* (2 September 1918 – 12 March 1969) was a British naval officer, civil servant and business executive, who served as Principal Private Secretary to two successive prime ministers, Harold Macmillan and Sir Alec Douglas-Home
Document 12: Anthony Eden: Robert Anthony Eden, 1st Earl of Avon, (12 June 1897 – 14 January 1977) was a British Conservative politician who served three periods as Foreign Secretary and then a relatively brief term as Prime Minister of the United Kingdom from 1955 to 1957.
Document 13: Anthony Eden hat: An "Anthony Eden" hat, or simply an "Anthony Eden", was a silk-brimmed, black felt Homburg of the kind favoured in the 1930s by Anthony Eden, later 1st Earl of Avon (1897–1977). Eden was a Cabinet Minister in the British National Government, holding the offices of Lord Privy Seal from 1934–1935 and Foreign Secretary 1935 to 1938. He was later Dominions Secretary from 1939–1940, War Secretary in 1940, Foreign Secretary from 1940–1945 and 1951–1955, and Prime Minister 1955 to 1957.
Document 14: Marienborg: Marienborg has been the official residence of Denmark's prime minister since 1962. It is frequently used for governmental conferences, summits and other official purposes, including the prime minister's new year speech. Unlike the residences of other heads of government and state (e.g. the White House, 10 Downing Street, La Moncloa and Élysée Palace), Marienborg does not serve as the government headquarters or contain the office of the prime minister, instead Christiansborg Palace is the location of the government departments.
Document 15: Winston Churchill: Sir Winston Leonard Spencer-Churchill, {'1': ", '2': ", '3': ", '4': "} (30 November 187424 January 1965) was a British statesman, army officer, and writer. He served as Prime Minister of the United Kingdom from 1940 to 1945 and again from 1951 to 1955. As a Member of Parliament (MP), he represented five constituencies over the course of his career. As Prime Minister, Churchill led Britain to victory during World War II. He led the Conservative Party for fifteen years from 1940 to 1955.
ground_truth: United Kingdom