user: Question: What is the average Extras for muttiah muralitharan, with less than 353 Runs Conceded?
Columns: ['Name', 'Overs Bowled', 'Maidens', 'Runs Conceded', 'Wickets', 'Extras', 'E.R.']
Types: ['text', 'real', 'real', 'real', 'real', 'real', 'real']
Sample row: ['Chaminda Vaas', 62.0, 3.0, 270.0, 5.0, 1.0, 4.35]
SQL:

assistant: SELECT AVG("Extras") FROM "Table" WHERE "Name" = 'muttiah muralitharan' AND "Runs Conceded" < 353.0;