And these same full-stack generators were the base of the [**FastAPI** Project Generators](project-generation.md){.internal-link target=_blank}.

/// info

Flask-apispec was created by the same Marshmallow developers.

///

/// check | "Inspired **FastAPI** to"

Generate the OpenAPI schema automatically, from the same code that defines serialization and validation.

///

        final List<String> versionList = new ArrayList<>();
        boolean isName = true;
        for (final String value : baseName.split("-")) {
            if (isName && value.length() > 0 && value.charAt(0) >= '0' && value.charAt(0) <= '9') {
                isName = false;
            }
            if (isName) {
                nameList.add(value);
            } else {
                versionList.add(value);

You would have **one single `engine` object** for all your code to connect to the same database.

{* ../../docs_src/sql_databases/tutorial001_an_py310.py ln[14:18] hl[14:15,17:18] *}

Using `check_same_thread=False` allows FastAPI to use the same SQLite database in different threads. This is necessary as **one single request** could use **more than one thread** (for example in dependencies).

* There can be **multiple processes** of the **same program** running at the same time.

If you check out the "task manager" or "system monitor" (or similar tools) in your operating system, you will be able to see many of those processes running.

//// tab | Python 3.10+

You can use the same builtin types as generics (with square brackets and types inside):

* `list`
* `tuple`
* `set`
* `dict`

And the same as with Python 3.8, from the `typing` module:

* `Union`
* `Optional` (the same as with Python 3.8)
* ...and others.

This is the same mechanism used when you give permissions while logging in with Facebook, Google, GitHub, etc:

<img src="/img/tutorial/security/image11.png">

## JWT token with scopes

Now, modify the token *path operation* to return the scopes requested.

* **Machine Learning**: it normally requires lots of "matrix" and "vector" multiplications. Think of a huge spreadsheet with numbers and multiplying all of them together at the same time.

But it's still part of the same **FastAPI** application/web API (it's part of the same "Python Package").

You can create the *path operations* for that module using `APIRouter`.

### Import `APIRouter`

You import it and create an "instance" the same way you would with the class `FastAPI`:

```Python hl_lines="1  3" title="app/routers/users.py"

Linux containers run using the same Linux kernel of the host (machine, virtual machine, cloud server, etc). This just means that they are very lightweight (compared to full virtual machines emulating an entire operating system).

If you pass a "callable" as a dependency in **FastAPI**, it will analyze the parameters for that "callable", and process them in the same way as the parameters for a *path operation function*. Including sub-dependencies.

That also applies to callables with no parameters at all. The same as it would be for *path operation functions* with no parameters.