are there other version of the song mentioned in the beginning?
Yes, by Leon Jackson.
When You Believe
"When You Believe" was recorded by "The X Factor" winner Leon Jackson in December 2007, with slightly altered lyrics in the second verse, removing some religious overtones within the song. 
who sings the song at the end of the wonder woman movie UNANSWERABLE is it a song? Yes. who wrote this song? Stephen Schwartz. who is the aforementioned person? He is an American musical theater lyricist and composer. is this song part of an album or is featured in a film? It is both. in which film was the song featured? "The Prince of Egypt". what are the singers who sang the song? Mariah Carey and Whitney Houston. who is the former? She is an American singer-songwriter and actress. what are some of her famous songs? "Hero", "Without You", "All I Want for Christmas Is You", "Fantasy", "Always Be My Baby", as well as "One Sweet Day", to name a few. was a music video made for the song (mentioned in the start)? Yes there was. who made this music video? UNANSWERABLE name few places where this song was performed live? The Oprah Winfrey Show, the 71st Annual Academy Awards and Carey's Sweet Sweet Fantasy Tour. what is the aforementioned show? It is an American daytime syndicated talk show.
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When You Believe [SEP] Leon Jackson version
"When You Believe" was recorded by "The X Factor" winner Leon Jackson in December 2007, with slightly altered lyrics in the second verse, removing some religious overtones within the song. The single was available to download from midnight after the result of the show on December 15, 2007, and a CD was rush-released mid-week, on December 19, 2007. This was unusual as most new singles were released on a Monday to gain maximum sales for the UK Singles Chart the following Sunday. Exceptions included the previous two "X Factor" winners whose were singles released in this fashion, in order for them to compete to be the Christmas number-one single, which they all became.