Question: Christmas Love Duets includes the John Lennon song that was released in what year as a single?

Context paragraphs:
Amarillo Ramp (For Robert Smithson): Amarillo Ramp (For Robert Smithson) is a studio album by Sonic Youth's Lee Ranaldo.  This album was for Robert Smithson, whose work as an artist was influential on Lee's artwork.  "Isolation" is a cover of the John Lennon song.

Life Begins at 40 (song): "Life Begins at 40" is a song by John Lennon.  It was written in 1980, the year that both Lennon and Ringo Starr turned 40 years of age.  Lennon recorded a demo of the song at his home, but it was not recorded at any of the sessions for his comeback album, "Double Fantasy."  Instead, he intended to give the song to Starr to record on his own forthcoming album, "Can't Fight Lightning."  The song's amiable country feel was well suited to Starr's singing style.  After Lennon's murder in December 1980, those plans were shelved.  However, Lennon's demo was eventually issued in 1998 on the "John Lennon Anthology" box set.

Every Man Has a Woman Who Loves Him: "Every Man Has a Woman Who Loves Him" is a Yoko Ono song from her "Double Fantasy" album with John Lennon.  The version released as a single, and on the compilation album "Every Man Has a Woman", is credited to Lennon, and has stripped away Ono's lead vocal, while bringing Lennon's backing vocal up in the mix (this version was also released as a bonus track on the CD reissue of "Milk and Honey").  The B-side featured "It's Alright" by Ono and Sean Lennon.  The last Lennon song to be released as a single, it failed to chart in either the United Kingdom or the United States.

Working Class Hero: A Tribute to John Lennon: Working Class Hero is a 1995 tribute album to Beatles singer/songwriter John Lennon.  It gets its name from a Lennon song of the same name.  Lindy Goetz, longtime manager of Red Hot Chili Peppers, acted as executive producer.  The album was released through Hollywood Records in support of the Humane Society of the United States.  According to the back cover of the CD, "Fifty percent of artist royalties, producer royalties, and of Hollywood Records' net profits from this album will be contributed to a dedicated fund administered by the Humane Society of the United States of America and will be used for spaying and neutering cats and dogs."  A PSA for the Humane society was released featuring the Chili Peppers to draw attention to the cause and the album.

Generation X (album): Generation X is the debut album of Generation X produced by Martin Rushent and released in 1978.  The album contained the UK hit single "Ready Steady Go" which reached No. 47 in the chart in March 1978.  The album itself peaked at No.29 on August 4.  When it was originally released in the USA, it featured a different track listing, omitting three songs and adding three songs from singles and "Gimme Some Truth", a rare studio cover of a John Lennon song.  The album was later remastered and re-released in 2002 with the original UK track listing, and six bonus tracks from singles.  "Kiss Me Deadly" was used in the soundtrack of the 1998 movie SLC Punk.

Back to Me (Cueshé album): Back to Me is the second album by Cueshé, released in 2006.  It contains a cover version of the John Lennon song, "Jealous Guy".

Happy Xmas (War Is Over): "Happy Xmas (War Is Over)" is a Christmas song with lyrics by John Lennon and Yoko Ono, released in 1971 as a single by John & Yoko/Plastic Ono Band with the Harlem Community Choir.  The lyrics are set to the traditional English ballad "Skewball".  It was the seventh single release by Lennon outside of his work with the Beatles.  The song reached number 4 in the UK, where its release was delayed until November 1972, and has periodically reemerged on the UK Singles Chart, most notably after Lennon's death in 1980, at which point it peaked at number 2.  Also a protest song against the Vietnam War, "Happy Xmas (War Is Over)" has since become a Christmas standard, frequently covered by other artists, appearing on compilation albums of seasonal music, and named in polls as a holiday favourite.

Oh My Love (disambiguation): "Oh My Love" is a 1971 John Lennon song.

Christmas Love Duets: Christmas Love Duets is an collaborative compilation album of Christmas music put together for the Christmas season by Filipino actor and singer Daniel Padilla with actress Kathryn Bernardo under Star Records.  The album features six songs with minus one including Jackson 5's "Give Love on Christmas Day," "Perfect Christmas," Judy Garland's "Have Yourself A Merry Little Christmas," "The Little Christmas Tree," Stevie Wonder's "Someday At Christmas," and John Lennon's "Happy Xmas (War Is Over)".

I'm Losing You (John Lennon song): "I'm Losing You" is a song written by John Lennon and released on his 1980 album "Double Fantasy".  It was completed in Bermuda in June 1980, after Lennon failed at an attempted telephone call to Yoko Ono.  The song is also available on the 1982 compilation "The John Lennon Collection", the 1998 boxset "John Lennon Anthology", the one disc compilation "Wonsaponatime", the 2005 two disc compilation "" and in 2010 for the "Gimme Some Truth" album.  The song was also featured in the 2005 musical "Lennon".

Supporting paragraphs: Christmas Love Duets Happy Xmas (War Is Over)
Answer: 1971