user: Question: Name the least valid poll for Munster
Columns: ['Constituency', 'Electorate', 'Turnout', 'Spoilt', 'Valid Poll', 'Quota', 'Seats', 'Candidates']
Types: ['text', 'real', 'text', 'text', 'real', 'text', 'real', 'real']
Sample row: ['Connacht–Ulster', 471577.0, '241,244 (51.2%)', '5,763 (2.4%)', 235481.0, '58,871', 3.0, 11.0]
SQL:

assistant: SELECT MIN("Valid Poll") FROM "Table" WHERE "Constituency" = 'Munster';