Question: Pumping Iron is a docudrama, released in what year, about the world of professional bodybuilding, with a focus on the 1975 IFBB Mr. Universe and 1975 Mr. Olympia competitions, the film also features segments on bodybuilder Francesco Columbu, an Italian actor, author, former champion bodybuilder and "World's Strongest Man" competitor?

Context paragraphs:
Lou Ferrigno: Louis Jude "Lou" Ferrigno ( ; born November 9, 1951) is an American actor, fitness trainer, fitness consultant and retired professional bodybuilder.  As a bodybuilder, Ferrigno won an IFBB Mr. America title and two consecutive IFBB Mr. Universe titles, and appeared in the bodybuilding documentary "Pumping Iron".  As an actor, he is best known for his title role in the CBS television series "The Incredible Hulk" and vocally reprising the role in subsequent animated and computer-generated incarnations.  He has also appeared in European-produced fantasy-adventures such as "Sinbad of the Seven Seas" and "Hercules", and as himself in the sitcom "The King of Queens" and the 2009 comedy "I Love You, Man".

Pumping Iron: Pumping Iron is a 1977 docudrama about the world of professional bodybuilding, with a focus on the 1975 IFBB Mr. Universe and 1975 Mr. Olympia competitions.  Directed by George Butler and Robert Fiore, it is inspired by a book of the same name by Butler and Charles Gaines, and nominally centers on the competition between Arnold Schwarzenegger and one of his primary competitors for the title of Mr. Olympia, Lou Ferrigno.  The film also features segments on bodybuilders Franco Columbu and Mike Katz, in addition to appearances by Ken Waller, Ed Corney, Serge Nubret, and other famous bodybuilders of the era.

1975 Mr. Olympia: The 1975 Mr. Olympia contest was an IFBB professional bodybuilding competition held November 4–11, 1975 in Pretoria, South Africa.  It was the 11th Mr. Olympia competition and the feature event of the 1975 IFBB International Congress.

Michael Kefalianos: Michael Kefalianos (Greek: Μιχάλης Κεφαλιανός ), first name also spelt Michalis and Mihalis, is a Greek bodybuilder of Greek and Australian dual citizenship who is an International Federation of BodyBuilders (IFBB) professional bodybuilder.  He is widely considered to be the best Greek bodybuilder.  In 2009 at the IFBB Australian Pro Grand Prix he placed fourth and became the first Greek bodybuilder to ever qualify for the Mr. Olympia competition, which is held in Las Vegas once a year in September.  He has since competed in more than 35 professional bodybuilding shows, with his career highlight the 2012 Mr. Europe win in Madrid, Spain.

2017 Mr. Olympia: The 2017 Mr. Olympia contest was a weekend long IFBB professional bodybuilding competition that was held on September 14 to 17, 2017, in Las Vegas, Nevada.  This was the 53rd Mr. Olympia competition celebrated.  The weekend competition is also known as the Joe Weider's Olympia Fitness and Performance Weekend.  While the main event was the competition for the title of Mr. Olympia, several other events were held which includes the Amateur competition and sports expo.

1981 Mr. Olympia: The 1981 Mr. Olympia contest was an IFBB professional bodybuilding competition held on October 10, 1981, at the Veterans Memorial Auditorium in Columbus, Ohio.  Following the 1980 Mr. Olympia controversy, a number of favored bodybuilders boycotted the event, including Frank Zane, Mike Mentzer, and Boyer Coe.  Franco Columbu followed Arnold Schwarzenegger's suit (1980 Mr Olympia) and came out of retirement for a one time appearance and won the Olympia.

Robby Robinson (bodybuilder): Robby Robinson (born May 24, 1946) is an American former professional bodybuilder.  Known early in his career as Robin Robinson, he is also known as The Black Prince and Mr Lifestyle.  He won various competitions including Mr America, Mr World, Mr Universe, Masters Olympia, and other titles of the International Federation of BodyBuilding & Fitness (IFBB), and appeared in several films (including the landmark docudrama "Pumping Iron") over a 27-year career as a professional bodybuilder, retiring from competition in 2001 at the age of 55.

Serge Nubret: Serge Nubret (October 6, 1938April 19, 2011) was a French professional bodybuilder, bodybuilding federation leader, movie actor and author.  He was awarded many bodybuilding titles, including IFBB Mr. Europe (1970) Tall, NABBA Mr. Universe (1976) and WBBG Pro.  Mr. World (1977).  Serge Nubret was nicknamed "The Black Panther."

Franco Columbu: Francesco Columbu (born in Ollolai, Sardinia, August 7, 1941) is an Italian actor, author, former champion bodybuilder and "World's Strongest Man" competitor.

Mr. Olympia: Mr. Olympia is the title awarded to the winner of the professional men's bodybuilding contest at Joe Weider's Olympia Fitness & Performance Weekend—an international bodybuilding competition that is held annually by the International Federation of BodyBuilding & Fitness (IFBB).  Joe Weider created the contest to enable the Mr. Universe winners to continue competing and to earn money.  The first Mr. Olympia was held on September 18, 1965, at the Brooklyn Academy of Music, New York City, with Larry Scott winning his first of two straight titles.

Supporting paragraphs: Pumping Iron Franco Columbu
Answer: 1977