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_57 (class VARCHAR, erp_w VARCHAR, call_sign VARCHAR)

### Question ###
What is the class of the translator with 10 ERP W and a call sign of w273bl?

### Accurate SQL ###

SELECT class FROM table_name_57 WHERE erp_w = 10 AND call_sign = "w273bl"