user: Question: Who directed the episodes that aired December 15, 1956? 
Columns: ['Series #', 'Season #', 'Title', 'Director', 'Writer(s)', 'Airdate']
Types: ['real', 'real', 'text', 'text', 'text', 'text']
Sample row: [45.0, 6.0, '" Indian White "', 'Ted Post Category:Articles with hCards', 'Tom Hanley, Jr. Category:Articles with hCards', 'October 27, 1956']
SQL:

assistant: SELECT "Director" FROM "Table" WHERE "Airdate" = 'December 15, 1956';