what is the {of} for {Darth Vader} has {performer} as {James Earl Jones} ?
What is the role of Darth Vader who is performed by James Earl Jones ?
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select distinct ?value  where {
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?statement <http://www.w3.org/1999/02/22-rdf-syntax-ns#object> <http://wikidata.dbpedia.org/resource/Q203960> .
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} 

What kind of role did James Earl Jones have when he played Darth Vader?