Question: What occupation do John M. Stahl and Grigori Aleksandrov have in common?

Context paragraphs:
Springtime (1947 film): Springtime or (Russian: Весна , "Vesna " ) is a 1947 Soviet musical-comedy film directed by Grigori Aleksandrov.

Isaak Dunayevsky: Isaak Osipovich Dunayevsky (Russian: "Исаак Осипович Дунаевский" ; also transliterated as Dunaevski or Dunaevsky; 30 January [O.S. 18 January] 1900 25 July 1955) was a Soviet film composer and conductor of the 1930s and 1940s, who achieved huge success in music for operetta and film comedies, frequently working with the film director Grigori Aleksandrov.  He is considered one of the greatest Soviet composers of all time.  Many of his songs are very well known and held in high regard in Russia and the former Soviet Union.

The General Line: The General Line, also known as Old and New (Russian: Старое и новое , "Staroye i novoye " ), is a 1929 Soviet drama film directed by Sergei Eisenstein and Grigori Aleksandrov.

Circus (1936 film): Circus (Russian: Цирк ; translit.  Tsirk) is a 1936 Soviet melodramatic comedy musical film.  It was directed by Grigori Aleksandrov and Isidor Simkov at the Mosfilm studios.  In his own words, it was conceived as "an eccentric comedy...a real side splitter."

John M. Stahl: John Malcolm Stahl (January 21, 1886 – January 12, 1950) was an American film director and producer.

Romance sentimentale: Romance sentimentale is a 1930 French film directed by Grigori Aleksandrov and Sergei M. Eisenstein.  The film is also known as Sentimental Romance (International English title).

The Composer Glinka: Kompozitor Glinka (Russian: Композитор Глинка ; English literal translation, Composer Glinka; American release title Man of Music) is a 1952 Soviet biographical film directed by Grigori Aleksandrov.

Tanya (1940 film): Tanya (Russian: Светлый путь , "Svetly put " , English: Bright Path ) is a 1940 musical-comedy film directed by Grigori Aleksandrov and based on the play "Cinderella" by Viktor Ardov.

Grigori Aleksandrov: Grigori Vasilyevich Aleksandrov or Alexandrov (Russian: Григо́рий Васи́льевич Алекса́ндров ; original family name was Мормоненко or Mormonenko; 23 January 1903 – 16 December 1983) was a prominent Soviet film director who was named a People's Artist of the USSR in 1947 and a Hero of Socialist Labor in 1973.  He was awarded the Stalin Prizes for 1941 and 1950.

October: Ten Days That Shook the World: October: Ten Days That Shook the World (Russian: Октябрь (Десять дней, которые потрясли мир) ; translit.  "Oktyabr': Desyat' dney kotorye potryasli mir") is a 1928 Soviet silent historical film by Sergei Eisenstein and Grigori Aleksandrov.  It is a celebratory dramatization of the 1917 October Revolution commissioned for the tenth anniversary of the event.  Originally released as October in the Soviet Union, the film was re-edited and released internationally as Ten Days That Shook The World, after John Reed's popular book on the Revolution.  In U.S. released by Amkino Corporation and First National (later was a subsidiary of Warner Bros.).

Supporting paragraphs: John M. Stahl Grigori Aleksandrov
Answer: film director