Task: Question Answering
Input (English): Passage: Lennon and Ono co-produced the song and album with Phil Spector, who commented on the track: "We knew what we were going to do ... It was going to be John making a political statement, but a very commercial one as well ... I always thought that 'Imagine' was like the national anthem." Lennon described his working arrangement with Ono and Spector: "Phil doesn't arrange or anything like that—[Ono] and Phil will just sit in the other room and shout comments like, 'Why don't you try this sound' or 'You're not playing the piano too well' ... I'll get the initial idea and ... we'll just find a sound from [there]."Recording took place on 27 May 1971 at Ascot Sound Studios, Lennon's newly built home studio at Tittenhurst Park, with string overdubs taking place on 4 July 1971 at the Record Plant, in New York City. Relaxed and patient, the sessions began during the late morning, running to just before dinner in the early evening. Lennon taught the musicians the chord progression and a working arrangement for "Imagine", rehearsing the song until he deemed the musicians ready to record. In his attempt to recreate Lennon's desired sound, Spector had some early tapings feature Lennon and Nicky Hopkins playing in different octaves on one piano. He also initially attempted to record the piano part with Lennon playing the white baby grand in the couple's all-white room. However, after having deemed the room's acoustics unsuitable, Spector abandoned the idea in favour of the superior environment of Lennon's home studio. They completed the session in minutes, recording three takes and choosing the second one for release. The finished recording featured Lennon on piano and vocal, Klaus Voormann on bass guitar, Alan White on drums and the Flux Fiddlers on strings.Issued by Apple Records in the United States in October 1971, "Imagine" became the best-selling single of Lennon's solo career. It peaked at number three on the Billboard Hot 100 and reached number one in Canada on the RPM national singles chart, remaining there for two weeks. Upon its release the song's lyrics upset some religious groups, particularly the line: "Imagine there's no heaven". When asked about the song during one of his final interviews, Lennon said he considered it to be as strong a composition as any he had written with the Beatles. He described the song's meaning and explicated its commercial appeal: "Anti-religious, anti-nationalistic, anti-conventional, anti-capitalistic, but because it is sugarcoated it is accepted ... Now I understand what you have to do. Put your political message across with a little honey." In an open letter to Paul McCartney published in Melody Maker, Lennon said that "Imagine" was "'Working Class Hero' with sugar on it for conservatives like yourself". On 30 November 1971, the Imagine LP reached number one on the UK chart. It became the most commercially successful and critically acclaimed album of Lennon's solo career. 
Question: What is the first name of the person whose best-selling single of his solo career was Imagine?
Output (English): John.