Remove unused imports

cps/web.py

@@ -41,7 +41,7 @@ from flask_login import login_user, logout_user, login_required, current_user, c
 from sqlalchemy.exc import IntegrityError, InvalidRequestError, OperationalError
 from sqlalchemy.sql.expression import text, func, true, false, not_, and_, or_
 from sqlalchemy.orm.attributes import flag_modified
-from werkzeug.exceptions import default_exceptions, InternalServerError
+from werkzeug.exceptions import default_exceptions
 from sqlalchemy.sql.functions import coalesce
 
 from .services.worker import WorkerThread