def as_sql(self, qn, connection):
lhs, lhs_params = self.process_lhs(qn, connection)<EOL>rhs, rhs_params = self.process_rhs(qn, connection)<EOL>params = lhs_params + rhs_params<EOL>rhs = self.lhs.field.encrypt_sql % rhs<EOL>return ('<STR_LIT>'.format(lhs, rhs)), params<EOL>
Responsible for creating the lookup with the digest SQL.

        Modify the right hand side expression to compare the value passed
        to a hash.