Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_name_2 ( year VARCHAR, numbers__quantity_ordered_ VARCHAR, fuel_propulsion VARCHAR, length VARCHAR )

### Question ###
What year was the diesel fuel propulsion, with a length of 40', and numbers (quanity ordered) of 3701-3729 (29 buses), retired?

### Accurate SQL ###

SELECT year AS Retired FROM table_name_2 WHERE fuel_propulsion = "diesel" AND length = "40'" AND numbers__quantity_ordered_ = "3701-3729 (29 buses)"