1class DatabaseError(Exception):
2    pass
3
4
5class UserNotFoundError(Exception):
6    pass
7
8
9def get_user_from_db(user_id: int) -> dict:
10    try:
11        result = _execute_query(
12            f"SELECT * FROM users WHERE id = {user_id}"
13        )
14        if not result:
15            raise UserNotFoundError(f"User {user_id} not found")
16        return result
17    except Exception as e:
18        raise DatabaseError("Database operation failed")
19
20
21def update_user_email(user_id: int, new_email: str) -> None:
22    try:
23        user = get_user_from_db(user_id)
24        _execute_query(
25            f"UPDATE users SET email = '{new_email}' WHERE id = {user_id}"
26        )
27    except DatabaseError:
28        raise RuntimeError("Failed to update email")
29
30
31def _execute_query(query: str):
32    pass  # заглушка