user: Question: Which Election has a Party of Democratic Party, and a Mayor of Leonardo Betti?
Columns: ['Municipality', 'Inhabitants', 'Mayor', 'Party', 'Election']
Types: ['text', 'real', 'text', 'text', 'real']
Sample row: ['Florence', 370702.0, 'Matteo Renzi', 'Democratic Party', 2009.0]
SQL:

assistant: SELECT "Election" FROM "Table" WHERE "Party" = 'Democratic Party' AND "Mayor" = 'Leonardo Betti';