### OpenAPI

**FastAPI** generiert ein „Schema“ mit all Ihren APIs unter Verwendung des **OpenAPI**-Standards zur Definition von APIs.

#### „Schema“

Ein „Schema“ ist eine Definition oder Beschreibung von etwas. Nicht der eigentliche Code, der es implementiert, sondern lediglich eine abstrakte Beschreibung.

#### API-„Schema“

    # For coverage
    assert UploadFile.__get_pydantic_core_schema__(str, lambda x: None) == {}


@needs_pydanticv1
def test_union_scalar_list():
    # For coverage
    # TODO: there might not be a current valid code path that uses this, it would
    # potentially enable query parameters defined as both a scalar and a list
    # but that would require more refactors, also not sure it's really useful

    ```

Notice that we declare the type of `current_user` as the Pydantic model `User`.

This will help us inside of the function with all the completion and type checks.

!!! tip
    You might remember that request bodies are also declared with Pydantic models.

    Here **FastAPI** won't get confused because you are using `Depends`.

!!! check

You can create production applications with **FastAPI** right now (and you have probably been doing it for some time), you just have to make sure that you use a version that works correctly with the rest of your code.

## Pin your `fastapi` version

Depending on your use case, you might prefer to use a different library, but if you asked me, I would probably suggest you try **Strawberry**.

Here's a small preview of how you could integrate Strawberry with FastAPI:

```Python hl_lines="3  22  25-26"

## Separating tests

In a real application, you probably would have your tests in a different file.

And your **FastAPI** application might also be composed of several files/modules, etc.

### **FastAPI** app file

Let's say you have a file structure as described in [Bigger Applications](bigger-applications.md){.internal-link target=_blank}:

```
.

# Development - Contributing

First, you might want to see the basic ways to [help FastAPI and get help](help-fastapi.md){.internal-link target=_blank}.

## Developing

If you already cloned the <a href="https://github.com/tiangolo/fastapi" class="external-link" target="_blank">fastapi repository</a> and you want to deep dive in the code, here are some guidelines to set up your environment.

### Virtual environment with `venv`

budget-insight.svg...

### Docs

* 📝 Update docs about async and response-model with more gender neutral language. PR [#1869](https://github.com/tiangolo/fastapi/pull/1869) by [@Edward-Knight](https://github.com/Edward-Knight).

### Translations

* 🌐 Add Russian translation for `docs/python-types.md`. PR [#3039](https://github.com/tiangolo/fastapi/pull/3039) by [@dukkee](https://github.com/dukkee).

  display: block;
  position: absolute;
  top: -10px;
  right: 0;
  font-size: 0.5rem;
  color: #999;
  background-color: #666;
  border-radius: 10px;
  padding: 0 10px;
  z-index: 10;
}

.announce-wrapper .sponsor-image {
  display: block;
  border-radius: 20px;
}

.announce-wrapper>div {
  min-height: 40px;
  display: flex;
  align-items: center;
}

.twitter {