Question: Walkin' is the debut mini-album by which South Korean singer-songwriter and record producer?

full_context: Document 1: Seohyun: Seo Ju-hyun (born June 28, 1991), known professionally as Seohyun, is a South Korean singer and actress. She debuted as a member of girl group Girls' Generation (and later its subgroup TTS) in August 2007, who went on to be one of the best-selling artists in South Korea and one of South Korea's most popular girl groups worldwide. Apart from her group's activities, she has established herself as an actress, notably through her participation in the original and Korean versions of stage musicals including "Moon Embracing the Sun", "Gone with the Wind" and "Mamma Mia". She also starred in the drama "". She debuted as a solo artist with her debut mini album, "Don't Say No", on January 17, 2017, making her the third Girls' Generation member to debut as a solo artist.
Document 2: Kim Chung-ha: Kim Chung-ha (born Kim Chan-mi on February 9, 1996), better known by the mononym Chungha, is a South Korean singer. She is best known for finishing fourth in Mnet's girl group survival show "Produce 101" and as a former member of the now disbanded South Korean girl group I.O.I.
Document 3: Lee Tae-min discography: The discography of the South Korean singer Lee Tae-min (most often credited as Taemin), consists of one studio album, three extended plays, six singles - five as lead artist and one as featured artist - and four appearances in soundtracks. Taemin released his first extended play, entitled "Ace" on August 18, 2014, along with its title track "Danger". On February 23, 2016, he released his first studio album, entitled "Press It", featuring the title track "Press Your Number". The album peaked at #1 on iTunes charts in Japan, Vietnam, Taiwan, Singapore, Thailand, Finland, and Hong Kong. It was also the #1 album sold on Hanteo and Synnara charts during its first week, in addition to selling more than 76,000 copies in its first month in South Korea.<ref name="Gaon Album Ranking Monthly (2/2016)"> </ref> "Press Your Number" debuted at #79 position on the Japan Hot 100, the first song by Taemin to appear on the chart. On July 27, 2016, released his first Japanese mini-album, entitled "Sayonara Hitori", including 4 new songs and "Press Your Number" (Japanese Version). The album sold more than 38,000 copies on the first day of release, and shot up to third place on the daily albums charts in Japan. Released his second Japanese mini-album, titled "Flame of Love", on July 18, 2017. After the release, the album immediately ranked #1 on Japan's daily albums charts, selling more than 45,000 copies.
Document 4: Luna (singer): Park Sun-young (born August 12, 1993), better known by her stage name Luna, is a South Korean singer, actress and presenter. She is best known as the main vocalist and lead dancer of South Korean girl group f(x). Luna made her solo debut with the extended play "Free Somebody" on May 31, 2016.
Document 5: Juniel: Choi Seo-ah (Korean: 최서아; born Choi Jun-hee on September 3, 1993) better known by her stage name Juniel (Hangul: 주니엘, often stylized as JUNIEL) is a South Korean singer-songwriter. She began her career in Japan before eventually debuting in South Korea. She was first known as 'Junie', but eventually changed her stage name to 'Juniel', which was derived from combining her name, Junie, and L for 'love'. She was also a member of the duo Romantic J with CNBLUE's Lee Jong-hyun under former label FNC Entertainment. In 2016, Juniel announced on her social media that she legally changed her native name from 최준희 (Choi Jun-hee) to 최서아 (Choi Seo-ah).
Document 6: Jung Joon Young 1st mini album: Jung Joon Young 1st mini album is the debut EP by South Korean rock singer, Jung Joon-young, released by CJ E&M on October 10, 2013. It consists of six songs containing a pre-released track "병이에요 (Spotless Mind)", the title track, "이별 10분 전 (The Sense of an Ending)", and two songs that he participated in writing and composing: "아는 번호 (Missed Call)" and "Take off Mask" and other two songs "정말? (Really?)", and "Be Stupid".
Document 7: IU (singer): Lee Ji-eun (Korean: 이지은 ; born May 16, 1993), better known by her stage name IU (Korean: 아이유 ), is a South Korean singer, songwriter and actress. While still in middle school, IU auditioned for various talent agencies with ambitions of becoming a singer. She signed with LOEN Entertainment in 2007 as a trainee and began her music career at the age of 15 with her debut album, "Lost and Found". Her follow-up albums, "Growing Up" and "IU...IM", brought her mainstream success, but it was through "Good Day" (Korean: 좋은 날 ), the lead single from her 2010 album "Real", that she achieved national stardom. "Good Day" spent five consecutive weeks at the top position of South Korea's Gaon Digital Chart and holds the record for spending the most number of weeks at No. 1 along with Psy's "Gangnam Style".
Document 8: Survivor (Elena Paparizou song): "Survivor" is a song recorded by Swedish Greek singer-songwriter Elena Paparizou. The song was released on 23 February 2014 as the second single from Paparizou's third English-language album, "One Life" (2014). It is also available in first disc of the 2014 Melodifestivalen album. The song was written by Bobby Ljunggren, Henrik Wikström, Karl-Ola Kjellholm and Sharon Vaughn. It participated in the 2014 Melodifestivalen where it came fourth in the final behind Alcazar, Ace Wilder and the winner, Sanna Nielsen.
Document 9: Someday (J-Walk album): Someday is the second album by Korean duo male group J-Walk. Korean male duo, Kim Jae Duc and Jang Su Won (former Sechskies members)is back with their Vol. 2 Someday. The album was released on October 2002, seven months after the first album. The featured song "Someday" contains fusion-style jazz and bossa flavors, with a sweet melody. The string part is performed by Korean top musicians. This album, again, is produced by Ahn Sung-Il, who was in charge of their debut album Suddenly.
Document 10: Luna discography: Luna (born Park Sun-young) is a South Korean singer, best known as a member of girl group f(x). Since 2009, she has released one extended play, twelve singles (including six collaborations and four as a featured artist), and fourteen soundtrack appearances. Her career as a solo artist began in May, 2016, with the release of her debut extended play, "Free Somebody".
Document 11: Walking With (album): Walking With () is the sixth solo studio album by South Korean pop singer-songwriter Kim Dong-ryool, and his seventh solo album overall. It was released on October 1, 2014 by the artist's label Music Farm and distributed by LOEN Entertainment. Guitarist (who has also been known as Lee Hyori's husband) and "Superstar K2" runner-up John Park participated on the album as featured artists. The album is the singer's first solo release since the holiday album "KimdongrYULE" (2011), and also his first studio album since "Monologue" (2008).
Document 12: My Love (J-Walk album): My Love is the third album by Korean duo male group J-Walk. In this album, J-Walk collaborated with their former Sechskies leader Eun Ji Won for a song called "My Love". The featured song "My Love" is a fast dance song with an electronic rhythm and "J-Walk style" ballad line.
Document 13: Suran (singer): Shin Su-ran (Hangul: 신수란), also known by her stage names Elena (Hangul: 엘에나) and Baily Shoo (Hangul: 베일리 슈), and better known by the mononym Suran (Hangul: 수란), is a South Korean singer-songwriter and record producer. She debuted as part of the duo, Lodia, on July 9, 2014, with the single "I Got A Feeling". In 2017, she has also appeared on MBC's "King of Mask Singer" (episodes 93–94) as a contestant named "Skip to the End, Hello".
Document 14: Walkin' (EP): Walkin' is the debut mini-album by South Korean singer Suran. It was released on June 2, 2017, by Million Market and distribuited by LOEN Entertainment. It consists of five songs, including "Wine" featuring rapper Changmo, previously released as a digital single, and the title track "1+1=0" featuring singer Dean.
Document 15: In the Wind (EP): In the Wind is the third mini-album played by the South Korean boy band B1A4 and was released by WM Entertainment on November 12, 2012. The track "Tried to Walk" was used as the lead single of the EP.
ground_truth: Shin Su-ran