user: Question: What is the Tie no when Chester is the away team?
Columns: ['Tie no', 'Home team', 'Score', 'Away team', 'Date']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['1', 'Blackpool', '2–1', 'Lincoln City', '25 November 1978']
SQL:

assistant: SELECT "Tie no" FROM "Table" WHERE "Away team" = 'Chester';