Simplify the following text for a Grade 7 native English-speaking person.
Original: James Moore , known as Slim Harpo , ( January 11 , 1924 â '' January 31 , 1970 ) was a famous blues musician born in Lobdell , Louisiana , USA .
Simplified: Slim Harpo ( January 11 , 1924 â `` January 31 , 1970 ) was an American blues musician .