Question: Which party did the English Prime Minister and subject of Barbara Learning lead from 1940 to 1955?

<P0-S0> Sir Winston Leonard Spencer-Churchill, {'1': ", '2': ", '3': ", '4': "} (30 November 187424 January 1965) was a British statesman, army officer, and writer. <P0-S1>  As Prime Minister, Churchill led Britain to victory during World War II. <P0-S2>  He served as Prime Minister of the United Kingdom from 1940 to 1945 and again from 1951 to 1955. <P0-S3>  As a Member of Parliament (MP), he represented five constituencies over the course of his career. <P0-S4>  He led the Conservative Party for fifteen years from 1940 to 1955. <SEP> <P1-S0> Barbara Leaming is a bestselling American biographer, whose subjects have included Roman Polanski, Orson Welles, Rita Hayworth, Marilyn Monroe, John F. Kennedy, Winston Churchill, and Jacqueline Kennedy Onassis. <SEP> <P2-S0> Han Myeong-sook (born March 24, 1944; Korean: 한명숙 ] ) was the Prime Minister of South Korea from April 2006 to March 2007. <P2-S1>  She is South Korea's first female prime minister (second female prime minister overall if the acting premiership of Chang Sang is included). <P2-S2>  She was from the United New Democratic Party (UNDP) as a member of the Korean National Assembly (representative) for Ilsan-gab, and is a graduate of Ewha Womans University in Seoul with a degree in French literature. <P2-S3>  She resigned as Prime Minister on March 7, 2007 and declared her presidential candidacy. <P2-S4>  But she did not succeed in the nominations. <P2-S5>  In 2008 she ran for parliament, but was not elected. <P2-S6>  However, in January 2012 she was elected leader of the main oppositional Democratic United Party (DUP) before the April legislative elections and became a member of parliament. <P2-S7>  But the liberals did not manage to defeat the ruling Saenuri Party and Han stepped down as party leader in April 2012. <P2-S8>  In August 2015, Han was convicted of receiving illegal donations at the amount of 900 million KRW, and sentence to two years in prison. <P2-S9>  She is ineligible to run for public office for ten years after her prison term. <P2-S10>  She became the first former prime minister of the Republic of Korea to serve a prison time. <SEP> <P3-S0> 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. <P3-S1>  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. <P3-S2>  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. <P3-S3>  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. <P3-S4>  He was re-elected with a narrow majority at the 1950 general election. <P3-S5>  In the following year, Attlee called a snap general election, hoping to increase his parliamentary majority. <P3-S6>  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. <P3-S7>  Attlee remains the longest-ever serving Leader of the Labour Party.