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Thomas Hart Benton  ( March 14 1782 April 10 1858 ) nicknamed Old Bullion was a U.S. Senator from  Missouri  and a staunch advocate of westward expansion of the United States .
 employee of: Thomas Hart Benton, Missouri
Given a phrase that describes the relationship between two words, extract the words and the lexical relationship between them. The output format should be "relation1: word1, word2; relation2: word3, word4". 
Option: cities of residence, top members employees, members, alternate names, origin, state or provinces of residence, title of person, spouse, city of headquarters, NA, founded by, state or province of headquarters, employee of, countries of residence, country of birth, founded, subsidiaries, country of headquarters 
Text: {0} 
Answer:
 employee of: Thomas Hart Benton, Missouri