* `fixedquery`: has the exact value `fixedquery`.
* `$`: ends there, doesn't have any more characters after `fixedquery`.

If you feel lost with all these **"regular expression"** ideas, don't worry. They are a hard topic for many people. You can still do a lot of stuff without needing regular expressions yet.

Now you know that whenever you need them you can use them in **FastAPI**.

This can be used as a quick shortcut if you have only one Pydantic model and want to remove some data from the output.

/// tip

But it is still recommended to use the ideas above, using multiple classes, instead of these parameters.

The most common way to do it is to have a file `requirements.txt` with the package names and their versions, one per line.

You would of course use the same ideas you read in [About FastAPI versions](versions.md){.internal-link target=_blank} to set the ranges of versions.

For example, your `requirements.txt` could look like:

```
fastapi[standard]>=0.113.0,<0.114.0

La forma más común de hacerlo es tener un archivo `requirements.txt` con los nombres de los paquetes y sus versiones, uno por línea.

Por supuesto, usarías las mismas ideas que leíste en [Acerca de las versiones de FastAPI](versions.md){.internal-link target=_blank} para establecer los rangos de versiones.

Por ejemplo, tu `requirements.txt` podría verse así:

```

* Then manually fix the remaining issues in the translation, so that it is a good translation.

    * Wenn Sie Pythons Typen kennen, wissen Sie, wie man Pydantic verwendet.
* Gutes Zusammenspiel mit Ihrer/Ihrem **<abbr title="Integrated Development Environment – Integrierte Entwicklungsumgebung: Ähnlich einem Code-Editor">IDE</abbr>/<abbr title="Ein Programm, das Fehler im Quellcode sucht">Linter</abbr>/Gehirn**:

    * No new schema definition micro-language to learn.
    * If you know Python types you know how to use Pydantic.
* Plays nicely with your **<abbr title="Integrated Development Environment: similar to a code editor">IDE</abbr>/<abbr title="A program that checks for code errors">linter</abbr>/brain**:

    * Eğer Python typelarını nasıl kullanacağını biliyorsan Pydantic kullanmayı da biliyorsundur.
* Kullandığın geliştirme araçları ile iyi çalışır **<abbr title="Integrated Development Environment, kod editörüne benzer">IDE</abbr>/<abbr title="Code errorlarınızı inceleyen program">linter</abbr>/brain**:

通过 **FastAPI** 你可以获得所有 **Pydantic**  (FastAPI 基于 Pydantic 做了所有的数据处理)：

* **更简单**：
    * 没有新的模式定义 micro-language 需要学习。
    * 如果你知道 Python types，你就知道如何使用 Pydantic。
* 和你 **<abbr title="集成开发环境，和代码编辑器类似">IDE</abbr>/<abbr title="一个检查代码错误的程序">linter</abbr>/brain** 适配:
    * 因为 pydantic 数据结构仅仅是你定义的类的实例；自动补全，linting，mypy 以及你的直觉应该可以和你验证的数据一起正常工作。
* 验证**复杂结构**:
    * 使用分层的 Pydantic 模型, Python `typing`的 `List` 和 `Dict` 等等。

		// 403, but in situations where there is a dependency
		// with the caller to take the client offline purpose
		// fully it should make sure to respond with '412'
		// instead, see cmd/storage-rest-server.go for ideas.
		if c.HealthCheckFn != nil && resp.StatusCode == http.StatusPreconditionFailed {
			err = fmt.Errorf("Marking %s offline temporarily; caused by PreconditionFailed with drive ID mismatch", c.url.Host)