user: Question: What is Myron Walwyn with a Territorial At-Large Constiuency's First Elected Date
Columns: ['Name', 'Party', 'Member of', 'First elected', 'Constiuency']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Dr D. Orlando Smith OBE, MD', 'NDP', 'Government', '1999-present', 'Territorial At-Large']
SQL:

assistant: SELECT "First elected" FROM "Table" WHERE "Constiuency" = 'Territorial At-Large' AND "Name" = 'Myron Walwyn';