Question: The supreme leader of North Korea and also the younger brother of Kim Jong- chul is the chairman for which party?

full_context: Document 1: Kimjongilia: Kimjongilia is a flower named after the late North Korean leader Kim Jong-il. It is a hybrid cultivar of tuberous begonia, registered as "Begonia" × "tuberhybrida" 'Kimjongilhwa'. When Kim Jong-il died in December 2011 the flower was used to adorn his corpse for public display. Despite its name, the Kimjongilia is not the official national flower of North Korea, which is the "Magnolia sieboldii". Another flower, Kimilsungia, is an orchid cultivar named after Kim Jong-il's father and predecessor, Kim Il-sung.
Document 2: Kim Han-sol: Kim Han-sol (Korean: 김한솔 , born 16 June 1995) is the eldest son of Kim Jong-nam and a grandson of the former North Korean ruler, Kim Jong-il. His father was the unofficial heir-apparent until 2001, when he fell out of favor with the regime after a failed attempt to secretly visit Japan's Disneyland in May 2001.
Document 3: Kim Yong-ju: Kim Yong-ju (Chosŏn'gŭl: 김영주; born 21 September 1920) is a North Korean politician and the younger brother of Kim Il-sung, who ruled North Korea from 1948 to 1994. Under his brother's rule, Kim Yong-ju held key posts in the Workers' Party of Korea during the 1960s and early 1970s, but he fell out of favor in 1974 following a power struggle with Kim Jong-il. Since 1998, he has held the ceremonial position of Honorary Vice President of the Presidium of the Supreme People's Assembly, North Korea's parliament.
Document 4: Kim Jong-man: Kim Jong-Man (born March 3, 1978), often anglicised to Jong-Man Kim, is a South Korean mixed martial artist who currently competes in the Featherweight division. While Kim has mostly fought in South Korea, he has also appeared in many Japanese promotions including, the Sengoku Raiden Championships, DEEP, Shooto, K-1 Hero's, and Russia's M-1 Global. He last fought at TOP FC - Original against Seung Hwa-Han.
Document 5: Chung Mong-koo: Chung Mong-koo (born March 19, 1938, in Gangwon Province) is the chairman of Hyundai Motor Group, a prominent car manufacturer in South Korea. The Hyundai Motor Group consists of 42 subsidiaries and is the second largest Chaebol in South Korea. Chung succeeded his father, Chung Ju-yung, the founder of the conglomerate known as the Hyundai Group. When the conglomerate split into several parts in 1999, Chung Mong-koo took over the Hyundai Motor division. He is the eldest surviving son of Chung Ju-yung's eight sons.
Document 6: Kim Jong-chul (poet): Kim Jong-chul (18 Feb 1947 - 5 July 2014) was a South Korean poet. He rose to fame in 1968 when he was awarded a prize by the Hankook newspaper for his poem "Sound of a Loom". In 1970 Kim won another prize with the Seoul Daily newspaper for his poem "Drowned Dreams". He is considered one of the most significant modern Korean poets.
Document 7: Kim Jong-nam: Kim Jong-nam (Chosŏn'gŭl: 김정남 ; Hancha: 金正男 , ] or ] ] ; 10 May 1971 – 13 February 2017) was the eldest son of North Korean leader Kim Jong-il. From roughly 1994 to 2001, he was considered the heir apparent to his father. He was thought to have fallen out of favour after embarrassing the regime in 2001 with a failed attempt to visit Tokyo Disneyland with a false passport, although Kim said his loss of favour was due to advocating reform.
Document 8: Yui Chul Nam: Yui Chul Nam (Korean: 남의철, born July 16, 1981, Korean name is Nam Yui-Chul) is a South Korean mixed martial artist. He formerly competed in the UFC's lightweight division after fighting in the Korean promotion Road FC.
Document 9: Kim Jong-un: Kim Jong-un (Chosŏn'gŭl: 김정은 ; ] or ] ] ; born 8 January 1982–84 or 5 July 1984) is the Chairman of the Workers' Party of Korea (WPK) and supreme leader of North Korea. Kim is the second child of Kim Jong-il (1941–2011) and Ko Yong-hui. Before taking power, Kim was rarely seen in public, and many of the activities of Kim and his government remain unknown. Even details such as what year he was born, and whether he did indeed attend a Western school under a pseudonym, are difficult to confirm.
Document 10: Song Hye-rang: Song Hye-rang (born 1935) is a North Korean defector and author. Her father was a wealthy South Korean landowner who moved to the North for political reasons, while her mother was an editor of the official North Korean newspaper "Rodong Shinmun". Song's younger sister Song Hye-rim, a popular actress, secretly began an affair with Kim Jong-il against his father Kim Il-sung's wishes in the late 1960s or early 1970s, which culminated in Hye-rim's forced divorce from her husband; Hye-rang first learned of the situation on 10 May 1971, when Kim came to her residence in the middle of the night and informed her that he had impregnated her younger sister. Five years later, Hye-rang would become responsible for raising Kim Jong-nam, the son resulting from that pregnancy; his father was unwilling to let him attend school for fear that the secret of his parentage would be revealed. Hye-rim moved into the household; she also brought her own son Ri Han-yong and daughter Ri Nam-ok to live with them, so that Jong-nam would not be lonely. Their lives were carefully managed by Kim Jong-il to ensure that his father would not find out about his continuing affair; they spent most of their time at residences in east Pyongyang or Chungsangdong, occasionally travelling overseas to Geneva and Moscow.
Document 11: Lee Jae-yong (businessman): Lee Jae-yong (이재용 ; born 23 June 1968), known professionally in the West as Jay Y. Lee, is a South Korean business magnate and the vice chairman of Samsung Group, serving as de facto head. He is the eldest child and only son of Lee Kun-hee, Chairman of Samsung, and is widely considered to be his father's future successor. He is referred to as the "Crown Prince of Samsung" by the South Korean media, and speaks Korean, English and Japanese. Lee is estimated to be worth US$7.9 billion, making him the third wealthiest person in South Korea.
Document 12: Kim Jong-chang: Kim Jong-chang (born 13 October 1948) served as the seventh governor of South Korea's Financial Supervisory Service from March 2008 to March 2011. He was named to his position on 27 March 2008, after nearly three decades in finance-related positions in the government and the government-owned Industrial Bank of Korea, and retired on 25 March 2011.
Document 13: Kim Jong-chul: Kim Jong-chul (born 25 September 1981) is a son of North Korean Kim Jong-il. His younger brother is Kim Jong-un, now the leader of North Korea. His older half-brother was Kim Jong-nam.
Document 14: Jang Song-thaek: Jang Song-thaek (] ; also romanized as Jang Sung-taek, Chang Sŏng-t'aek and other variations; January or February 1946 – 12 December 2013) was a leading figure in the government of North Korea. He was married to Kim Kyong-hui, the only daughter of former North Korean supreme leader Kim Il-sung, the only sister of former North Korean supreme leader Kim Jong-il and the aunt of Kim Jong-un, the supreme leader of North Korea.
Document 15: Kim Pyong-il: Kim Pyong-il (] ; born 10 August 1954) is the younger paternal half-brother of the former leader of North Korea, Kim Jong-il, and the son of former leader Kim Il-sung. He is the current ambassador of North Korea to the Czech Republic.
ground_truth: Workers' Party of Korea