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_17 ( entrant VARCHAR, points VARCHAR, chassis VARCHAR, year VARCHAR )

### Question ###
What entrant had a Maserati 250F chassis and fewer than 6 points before 1957?

### Accurate SQL ###

SELECT entrant FROM table_name_17 WHERE chassis = "maserati 250f" AND year < 1957 AND points < 6