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1. Import from `sqlmodel` everything we will use, including the new `select()` function.
2. Create the `Hero` class model, representing the `hero` table.
3. Create the **engine**, we should use a single one shared by all the application code, and that's what we are doing here.
4. Create all the tables for the models registered in `SQLModel.metadata`.
This also creates the database if it doesn't exist already.
5. Create each one of the `Hero` objects.
You might not have this in your version if you had already created the data in the database.
6. Create a new **session** and use it to `add` the heroes to the database, and then `commit` the changes.
7. Create a new **session** to query data.
/// tip
Notice that this is a new **session** independent from the one in the other function above.
But it still uses the same **engine**. We still have one engine for the whole application.
///
8. Use the `select()` function to create a statement selecting all the `Hero` objects.
This selects all the rows in the `hero` table.
9. Use `session.exec(statement)` to make the **session** use the **engine** to execute the internal SQL statement.
This will go to the database, execute that SQL, and get the results back.
It returns a special iterable object that we put in the variable `results`.
This generates the output:
```
INFO Engine BEGIN (implicit)
INFO Engine SELECT hero.id, hero.name, hero.secret_name, hero.age
FROM hero
INFO Engine [no key 0.00032s] ()
```
10. Iterate for each `Hero` object in the `results`.
11. Print each `hero`.
The 3 iterations in the `for` loop will generate this output:
```
id=1 name='Deadpond' age=None secret_name='Dive Wilson'
id=2 name='Spider-Boy' age=None secret_name='Pedro Parqueador'
id=3 name='Rusty-Man' age=48 secret_name='Tommy Sharp'
```
12. At this point, after the `with` block, the **session** is closed.
This generates the output:
```
INFO Engine ROLLBACK
```
13. Add this function `select_heroes()` to the `main()` function so that it is called when we run this program from the command line.
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