Question: The San Francisco Demons were part of a failed professional American football league which played one season in what year?

Context paragraphs:
Derrick Gardner (American football): Derrick A. Gardner (born March 10, 1977) is a former American football defensive back who played one season with the Atlanta Falcons of the National Football League (NFL).  He played college football at the University of California, Berkeley and attended Skyline High School in Oakland, California.  He was also a member of the Rhein Fire, San Francisco Demons and Los Angeles Avengers.

Albrey Battle: Albrey Battle (born October 21, 1976) is a former American football defensive lineman who played eight seasons in the Arena Football League with the San Jose SaberCats and Arizona Rattlers.  He played college football at Arizona State University and attended Poway High School in Poway, California.  He was also a member of the Tennessee Titans and San Francisco Demons.

San Francisco Demons: The San Francisco Demons (originally named San Jose Demons) were a short-lived springtime American football team based in San Francisco, California.  This team was part of the failed XFL begun by Vince McMahon of World Wrestling Entertainment and by NBC, a major television network in the United States.  Originally they were to be based in San Jose but prior to the start of the season they were moved to San Francisco.  They were in the Western Division with the Los Angeles Xtreme, Las Vegas Outlaws and Memphis Maniax.

Mike Adams (wide receiver): Michael Christopher Adams (born March 25,1974) is a former gridiron football wide receiver and return specialist from Grand Prairie (Dalworth),Texas, also the home of NFL Hall of Famer and former Redskin Charles Taylor.  He was drafted by the Pittsburgh Steelers of the National Football League, but only played for one season.  He later played for the BC Lions of the Canadian Football League in 2000 and the defunct Xtreme Football League (XFL) San Francisco Demons in 2001.

Travis Moore: Travis Moore (born August 5, 1970) is a former professional Canadian football slotback and current receivers coach for the Ottawa Redblacks of the Canadian Football League.  As a player, Moore played 10 seasons for the Calgary Stampeders and the Saskatchewan Roughriders, winning two Grey Cup championships with the Stampeders in 1998 and 2001.  He also played in the one and only XFL season as a Wide Receiver for the San Francisco Demons team that competed in the league's championship game.

Arrington Jones: Arrington Jones III (born February 16, 1959) is a former American football running back who played one season with the San Francisco 49ers of the National Football League (NFL).  He was drafted by the San Francisco 49ers in the fifth round of the 1981 NFL Draft.  He played college football at Winston-Salem State University and attended John Marshall High School in Richmond, Virginia.  Jones was also a member of the Washington Federals of the United States Football League (USFL).  He was a member of the San Francisco 49ers team that won Super Bowl XVI and has been a coach on several collegiate teams.

Tom Mitchell (American football): Thomas Gordon ("Tom") Mitchell (August 22, 1944 – July 16, 2017) was a college and professional American football player.  A 6'2", 219 lb .  tight end from Bucknell University, Mitchell played one season (1966) for the American Football League's Oakland Raiders, and ten seasons (1968–1977) in the National Football League for the Baltimore Colts and the San Francisco 49ers.  He was nicknamed "The Crocodile" and his pouring a pitcher of beer on the head of author George Plimpton is recounted in the book "Mad Ducks and Bears".  He died of cancer at the age of 72 in 2017.

James Hundon: James Henry Hundon (born April 9, 1971) is a former American football wide receiver who played four seasons with the Cincinnati Bengals of the National Football League.  He first enrolled at City College of San Francisco before transferring to Portland State University.  He attended Jefferson High School in Daly City, California.  Hundon was also a member of the San Jose SaberCats, San Francisco Demons, Toronto Argonauts and Calgary Stampeders.  He was featured on the cover of Sports Illustrated following week one of the XFL season.

XFL: The XFL was a professional American football league which played one season in 2001.  It was operated as a joint venture between the World Wrestling Federation (WWF, now known as WWE) and NBC.  The XFL was conceived as an outdoor football league that would take place during the NFL off-season, and promoted as having fewer rules and encouraging rougher play than other major leagues.  The league had eight teams in two divisions, including major markets and those not directly served by the NFL, including Birmingham, Las Vegas, Los Angeles, Memphis, and Orlando.  The XFL operated as a single entity, with all teams centrally owned by the league.

Los Angeles Xtreme: The Los Angeles Xtreme was a professional American football team based in Los Angeles, California.  The team was a member of the XFL begun by Vince McMahon of World Wrestling Entertainment and by NBC, a major television network in the United States.  The team played its home games in the Los Angeles Memorial Coliseum in the spring of 2001.  They were in the XFL's Western Division with the San Francisco Demons, the Memphis Maniax and the Las Vegas Outlaws.  The team had the league's best passing offense and was nicknamed "L.A.X." as a pun on the IATA code for Los Angeles International Airport.  They finished the season in 1st place with a 7-3 record and defeated the Chicago Enforcers in the Playoffs and the San Francisco Demons in the Million Dollar Game with a score of 38-6 to win the league's sole Championship.

Supporting paragraphs: San Francisco Demons XFL
Answer: 2001