user: Question: What is the Yogi Bear that aired on 1959.12.21?
Columns: ['Nº', 'Ep', 'Huckleberry Hound', 'Pixie and Dixie', 'Yogi Bear', 'Air date', 'Credited animators']
Types: ['real', 'real', 'text', 'text', 'text', 'text', 'text']
Sample row: [27.0, 1.0, '"Ten Pin Alley"', '"Hi Fido"', '"Show Biz Bear"', '1959.09.14', 'Ed Love , Manuel Perez, Don Patterson']
SQL:

assistant: SELECT "Yogi Bear" FROM "Table" WHERE "Air date" = '1959.12.21';