Question: Which Louisiana State senator has held a position in the 4th U. S. Congress?
Answer(s):
answer: Edward Livingston

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WHERE {
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FILTER (!isLiteral(?x) OR lang(?x) = '' OR langMatches(lang(?x), 'en'))
ns:m.04ly1 ns:government.political_district.representatives ?y .
?y ns:government.government_position_held.office_holder ?x .
?y ns:government.government_position_held.office_position_or_title ns:m.02_7l8y .
?x ns:government.politician.government_positions_held ?c .
?c ns:government.government_position_held.legislative_sessions ns:m.01grpc . 
}