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_51 (general_classification VARCHAR, winner VARCHAR, stage VARCHAR)

### Question ###
What is guido bontempi's general classification when he has a stage of 6?

### Accurate SQL ###

SELECT general_classification FROM table_name_51 WHERE winner = "guido bontempi" AND stage = "6"