Question: Who was one of the best-known U.S. artists of the middle 20th century and was the subject of  a 2013 British documentary film directed by Eleanor Yule? 
Sentence (from "Albert Jay Nock"): He was an outspoken opponent of the New Deal, and served as a fundamental inspiration for the modern libertarian and Conservative movements, cited as an influence by William F. Buckley, Jr. He was one of the first Americans to self-identify as "libertarian".
Relevant evidence: No