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Billy Butler ( born June 7 , 1945 , Chicago , Illinois ) is an American soul singer and songwriter active principally in the 1960s and early 1970s .
 Billy Butler, Chicago, Illinois, American
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
 Billy Butler, Chicago, Illinois, American