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formula10/database/common_query_util.py

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+from formula10.database.model.race_result import RaceResult
+from formula10.database.model.user import User
+from formula10 import db
+
+def race_has_result(race_name: str) -> bool:
+    return db.session.query(RaceResult).filter_by(race_name=race_name).first() is not None
+
+
+def user_exists(user_name: str) -> bool:
+    return db.session.query(User).filter_by(name=user_name).first() is not None