Question: What occupation did William Friedkin and Wang Quan'an share?

Context paragraphs:
Weaving Girl: Weaving Girl is a 2009 Chinese film directed by Wang Quan'an.  Wang's fourth feature film, "Weaving Girl" stars Wang's frequent collaborator and former partner, actress Yu Nan.

William Friedkin: William Friedkin (born August 29, 1935) is an American film director, producer and screenwriter best known for directing "The French Connection" in 1971 and "The Exorcist" in 1973; for the former, he won the Academy Award for Best Director.  Some of his other films include "Sorcerer", "Cruising", "To Live and Die in L.A.", "Jade", "Rules of Engagement", "The Hunted", "Bug", and "Killer Joe".

Jia Zhangke: Jia Zhangke (born 24 May 1970) is a Chinese film director and screenwriter.  He is generally regarded as a leading figure of the "Sixth Generation" movement of Chinese cinema, a group that also includes such figures as Wang Xiaoshuai, Lou Ye, Wang Quan'an and Zhang Yuan.

Jingzhe (film): Jingzhe is a 2004 Chinese film directed by Wang Quan'an.  The film is Wang's second feature and sees him reuniting with actress Yu Nan.  "Jingzhe" is also known by its original international title, The Story of Ermei.

White Deer Plain (film): White Deer Plain () is a 2011 Chinese drama film directed by Wang Quan'an and based on the novel of the same name by Chen Zhongshi.  The film competed in competition for the Golden Bear at the 62nd Berlin International Film Festival, where Lutz Reitemeier won the Silver Bear for Outstanding Artistic Achievement for his photography.

To Live and Die in L.A. (film): To Live and Die in L.A. is a 1985 American action thriller film directed by William Friedkin and based on the novel by former U.S. Secret Service agent Gerald Petievich, who co-wrote the screenplay with Friedkin.  The film features William Petersen, Willem Dafoe and John Pankow among others.  Wang Chung composed and performed the original music soundtrack.  The film tells the story of the lengths to which two Secret Service agents go to arrest a counterfeiter.

Lunar Eclipse (film): Lunar Eclipse is a 1999 Chinese film and the directorial debut from Sixth Generation director Wang Quan'an.  It is also the feature film debut of Wang's most frequent collaborator/muse Yu Nan.  Unlike his next two films, which focus on rural communities, "Lunar Eclipse" is an urban drama following the wife of a newlywed couple (Yu Nan) who becomes mesmerized by an amateur photographer (Wu Chao) who claims to have once been in love with a woman who looked just like her.  The film was produced by the Beijing Film Studio.

Wang Quan'an: Wang Quan'an () (b. 1965) is a Sixth Generation Chinese film director.  Wang was born in Yan'an, China.  He graduated from the Beijing Film Academy in 1991.  He had a ten-year relationship with actress and muse Yu Nan, which ended in 2009.

Apart Together: Apart Together () is a 2010 Chinese drama film directed by Wang Quan'an.  It was nominated for the Golden Bear at the 60th Berlin International Film Festival and won the Best Screenplay award.

Tuya's Marriage: Tuya's Marriage is a 2006 Chinese film directed by Wang Quan'an.

Supporting paragraphs: William Friedkin Wang Quan'an
Answer: film director