Question: Which writer is Russian, Jack Schaefer or Boris Pilnyak?

Context paragraphs:
Boris Paichadze Dinamo Arena: Boris Paichadze Dinamo Arena, formerly known as Lenin Dinamo Stadium and later Boris Paichadze National Stadium, is a stadium in Tbilisi, Georgia, and the home stadium of Dinamo Tbilisi, Georgia national rugby union team and Georgia national football team.  With a capacity of 54,549, the stadium is the largest in Georgia.  Built in 1976 by the Georgian architect Gia Kurdiani, the Dinamo Arena was named Vladimir Ilyich Lenin Dinamo Stadium after Russian Communist leader but later, in 1995 was renamed to Boris Paichadze National Stadium after the famous Georgian football player Boris Paichadze.  Prior to the construction of Boris Paichadze Dinamo Arena, the home stadium of Dinamo Tbilisi was the Central Stadium with an approximate capacity of 35,000 spectators.  The demand for a much bigger stadium was increased with the successful performance of Dinamo Tbilisi in the mid 1970s.  After the inauguration of the stadium, it became the third-largest in the Soviet Union, with a capacity of 74,354 spectators.

Shane (novel): Shane is a western novel by Jack Schaefer published in 1949.  It was initially published in 1946 in three parts in "Argosy" magazine, and originally titled "Rider from Nowhere".  The novel has been translated into over 30 languages, and was adapted into the famous 1953 film starring Alan Ladd.

Shane (TV series): Shane is an American Western television series aired in 1966 and based on the 1949 book of the same name by Jack Schaefer (there had also been a 1953 film of the novel, "Shane").  The series starred David Carradine as the title character, a former gun fighter and sometimes outlaw who takes on work as a hired-hand at the ranch of a widowed woman, her son, and her father.  The series, which aired on ABC, was filmed as a continuing story.

Boris Pilnyak: Boris Pilnyak (Russian: Бори́с Пильня́к ) (October 11 [O.S. September 29] 1894 – April 21, 1938) was a Russian writer.

Jack Schaefer: Jack Warner Schaefer (November 19, 1907 – January 24, 1991) was an American writer known for his Westerns.  His best-known work is "Shane", which was made into the film "Shane", and the short story "Stubby Pringle's Christmas" (1964).

Shane (film): Shane is a 1953 American Technicolor Western film from Paramount Pictures, noted for its landscape cinematography, editing, performances, and contributions to the genre.  The picture was produced and directed by George Stevens from a screenplay by A. B. Guthrie Jr., based on the 1949 novel of the same name by Jack Schaefer.  Its Oscar-winning cinematography was by Loyal Griggs.  "Shane" stars Alan Ladd and Jean Arthur in the last feature (and only color) film of her career.  The film also stars Van Heflin and features Brandon deWilde, Jack Palance, Emile Meyer, Elisha Cook Jr., and Ben Johnson.

Advance to the Rear: Advance to the Rear is a light-hearted 1964 American western comedy film set in the American Civil War.  It stars Glenn Ford, Stella Stevens and Melvyn Douglas and is directed by George Marshall.  The film is based on the 1957 novel "Company of Cowards" by Jack Schaefer, with the film having that title in pre-production and when released in the United Kingdom.  However, the novel had none of the comedic elements of the film which retained only the basic idea of a unit formed out of men who had been court-martialed for cowardice and sent out west as well as some character names.

Tribute to a Bad Man: Tribute to a Bad Man is a 1956 western film starring James Cagney about a rancher whose harsh enforcement of frontier justice alienates the woman he loves.  It was directed by Robert Wise and based on the short story "Hanging's for the Lucky" by Jack Schaefer, the author of "Shane".

Monte Walsh (1970 film): Monte Walsh is a 1970 film directed by cinematographer William A. Fraker.  His directorial debut, it stars Lee Marvin, Jeanne Moreau and Jack Palance.  The name "Monte Walsh" is taken from the title of a 1963 western novel by Jack Schaefer, but the film has little to do with the plot of Schaefer's book.  The film was set in Harmony, Arizona.  A made-for-TV remake was set in Wyoming and directed by Simon Wincer, with Tom Selleck and Isabella Rossellini playing the parts of Monte and Martine.  The story has elements of a tragedy.  The song played over the opening credits is "The Good Times Are Comin' " by Mama Cass, with music and lyrics by John Barry and Hal David.

Monte Walsh (2003 film): Monte Walsh is a 2003 Western television film directed by Simon Wincer and starring Tom Selleck, Isabella Rosellini, and Keith Carradine.  Loosely based on the 1963 Western novel "Monte Walsh" by Jack Schaefer, the film is about two long-time cowboys whose solitary and predictable lives on the range are inexorably changed when a fellow cowhand becomes involved with rustling and killing.  Set in Wyoming and filmed in Alberta, Canada, "Monte Walsh" is a remake of the 1970 theatrical film "Monte Walsh", starring Lee Marvin.  The script is nearly word-for-word identical to the original (original screenwriters David Zelag Goodman and Lukas Heller are credited) and a lot of set-ups and shots are the same as well, but Selleck plays a much more amiable and kind Walsh, to the point that some of the harsher lines attributed to Marvin's Walsh are given to other characters to soften the title character's personality to match Selleck's more affable style.  In 2003, "Monte Walsh" received an Emmy Award nomination for Outstanding Sound Editing for a Miniseries, Movie or a Special, and in 2004, the film received the Western Heritage Awards Bronze Wrangler for Outstanding Television Feature Film.

Supporting paragraphs: Jack Schaefer Boris Pilnyak
Answer: Boris Pilnyak