What is the average fleet size for the Shunter type introduced in 1959?
CREATE TABLE table_name_3 (fleet_size INTEGER, type VARCHAR, introduced VARCHAR)
SELECT AVG(fleet_size) FROM table_name_3 WHERE type = "shunter" AND introduced = "1959"
<s>[INST] Write mssql query to answer the following question given the database schema. Schema: CREATE TABLE table_name_3 (fleet_size INTEGER, type VARCHAR, introduced VARCHAR) Question: What is the average fleet size for the Shunter type introduced in 1959? [/INST] SELECT AVG(fleet_size) FROM table_name_3 WHERE type = "shunter" AND introduced = "1959" </s>