Question: Upton Sinclair and Nora Ephron were both writers from which country?

Context paragraphs:
Imaginary Friends (play): Imaginary Friends is a play by Nora Ephron.  It includes songs with music by Marvin Hamlisch and lyrics by Craig Carnelia.  This was Ephron's first stage play.

Mental Radio: Mental Radio: Does it work, and how?  (1930) was written by the American author Upton Sinclair and initially self-published.  This book documents Sinclair's test of psychic abilities of Mary Craig Sinclair, his second wife, while she was in a state of profound depression with a heightened interest in the occult.  She attempted to duplicate 290 pictures which were drawn by her brother.  Sinclair claimed Mary successfully duplicated 65 of them, with 155 "partial successes" and 70 failures.  The experiments were not conducted in a controlled scientific laboratory environment.

Upton Sinclair House: The Upton Sinclair House, located at 464 N. Myrtle Avenue, Monrovia, California, was the home of American novelist Upton Sinclair between 1942 and 1966.  It is a 1923 Neo-Mediterranean building in a district of similar houses, located in suburban Los Angeles, in the San Gabriel Valley.  Most of his later works were written while he lived here.  He had converted the rear garage into his study.  The grounds also include a concrete vault where he kept all his papers.

Upton Sinclair: Upton Sinclair Jr. (September 20, 1878 – November 25, 1968) was an American writer who wrote nearly one hundred books and other works in several genres.  Sinclair's work was well known and popular in the first half of the twentieth century, and he won the Pulitzer Prize for Fiction in 1943.

This Is My Life (1992 film): This Is My Life is a 1992 film that marked the directorial debut of screenwriter Nora Ephron.  The screenplay, written by Ephron and her sister, Delia Ephron, is based on the book, "This Is Your Life", by Meg Wolitzer.

Nora Ephron: Nora Ephron ( ; May 19, 1941 – June 26, 2012) was an American writer and filmmaker.  She is best known for her romantic comedy films and was nominated three times for the Academy Award for Best Writing: for "Silkwood" (1983), "When Harry Met Sally..." (1989), and "Sleepless in Seattle" (1993).  She won a BAFTA Award for Best Original Screenplay for "When Harry Met Sally...".  She sometimes wrote with her sister Delia Ephron.  Her last film was "Julie & Julia."  She also co-authored the Drama Desk Award–winning theatrical production "Love, Loss, and What I Wore".  In 2013, Ephron received a posthumous Tony Award nomination for Best Play for "Lucky Guy".

My Blue Heaven (1990 film): My Blue Heaven is a 1990 American crime comedy film directed by Herbert Ross, written by Nora Ephron, and starring Steve Martin, Rick Moranis, and Joan Cusack.  This is the third film in which Martin and Moranis starred together.  It has been noted for its relationship to "Goodfellas", which was released one month later.  Both films are based upon the life of Henry Hill, although the character is renamed "Vincent 'Vinnie' Antonelli" in "My Blue Heaven".  "Goodfellas" was based upon the book "Wiseguy" by Nicholas Pileggi, while the screenplay for "My Blue Heaven" was written by Pileggi's wife Nora Ephron, and much of the research for both works was done in the same sessions with Hill.

You've Got Mail: You've Got Mail is a 1998 American romantic comedy-drama film directed by Nora Ephron, co-written by Nora and Delia Ephron, and starring Tom Hanks and Meg Ryan.  The film is about two people in an online romance who are unaware that they are also business rivals.  It marks the third coupling of stars Tom Hanks and Meg Ryan, who had previously appeared together in "Joe Versus the Volcano" (1990) and "Sleepless in Seattle" (1993).

Zuzanna Szadkowski: Zuzanna Szadkowski (born October 22, 1978) is a Polish-American actress, known for her role as Dorota Kishlovsky on the CW teen drama series "Gossip Girl".  Szadkowski also appeared on "The Sopranos", "", and "Guiding Light".  She made her New York Stage debut in Nora Ephron and Delia Ephron's "Love, Loss, and What I Wore" in which she appeared in a record-breaking five all-star casts.  Her surname pronouced as ""shad-kawv-skee"".

Take Her, She's Mine: Take Her, She's Mine is a 1963 comedy film starring James Stewart and Sandra Dee based on the 1961 Broadway comedy written by Henry Ephron and Phoebe Ephron.  The film was directed by Henry Koster with a screenplay by Nunnally Johnson.  It also features an early film score by prolific composer Jerry Goldsmith.  The character of Mollie, played by Elizabeth Ashley on Broadway and in the film by Sandra Dee, was based on the then 22-year-old Nora Ephron.  Ashley's performance won her a Tony Award for Best Featured Actress in a Play and served as the launchpad for her career.

Supporting paragraphs: Nora Ephron Upton Sinclair
Answer: American