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_35 ( asts INTEGER, school_country VARCHAR, rebs VARCHAR )

### Question ###
What's the sum of asts for boston college with a rebs over 63?

### Accurate SQL ###

SELECT SUM(asts) FROM table_name_35 WHERE school_country = "boston college" AND rebs > 63