who is the aforementioned person?
He is an American musical theater lyricist and composer.
Stephen Schwartz (composer)
Stephen Lawrence Schwartz (born March 6, 1948) is an American musical theater lyricist and composer. 
who sings the song at the end of the wonder woman movie UNANSWERABLE is it a song? Yes. who wrote this song? Stephen Schwartz.
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Stephen Schwartz (composer) [SEP] Introduction
Stephen Lawrence Schwartz (born March 6, 1948) is an American musical theater lyricist and composer. In a career spanning over four decades, Schwartz has written such hit musicals as "Godspell" (1971), "Pippin" (1972), and "Wicked" (2003). He has contributed lyrics to a number of successful films, including "Pocahontas" (1995), "The Hunchback of Notre Dame" (1996), "The Prince of Egypt" (1998, music and lyrics), and "Enchanted" (2007). Schwartz has won the Drama Desk Award for Outstanding Lyrics, three Grammy Awards, three Academy Awards, and has been nominated for six Tony Awards. He received the 2015 Isabelle Stevenson Award, a special Tony Award, for his commitment to serving artists and fostering new talent.