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_20 (class VARCHAR, stages_won VARCHAR, position VARCHAR)

### Question ###
What is the class that that won 2 stages and has a position of DNF?

### Accurate SQL ###

SELECT class FROM table_name_20 WHERE stages_won = "2" AND position = "dnf"