```Python hl_lines="1  4"
{!../../docs_src/python_types/tutorial009.py!}
```

`str` yerine `Optional[str]` kullanmak editorün bu değerin her zaman `str` tipinde değil bazen `None` tipinde de olabileceğini belirtir ve hataları tespit etmemizde yardımcı olur.

#### Generic tipler

Köşeli parantez içinde tip parametreleri alan bu türler, örneğin:

Dokümantasyona tekrardan çok nadir olarak geleceksin.

Editörün sana nasıl yardım ettiğine bir bak:

* <a href="https://code.visualstudio.com/" class="external-link" target="_blank">Visual Studio Code</a> ile:

![editor support](https://fastapi.tiangolo.com/img/vscode-completion.png)

* <a href="https://www.jetbrains.com/pycharm/" class="external-link" target="_blank">PyCharm</a> ile:

  internal fun completeEdit(
    editor: Editor,
    success: Boolean,
  ) {
    val entry = editor.entry
    check(entry.currentEditor == editor)

    // If this edit is creating the entry for the first time, every index must have a value.
    if (success && !entry.readable) {
      for (i in 0 until valueCount) {
        if (!editor.written!![i]) {
          editor.abort()

## Tasarım

Sonrasında, (**FastAPI** kullanan bir geliştirici olarak) sahip olmak istediğim "API"ı tasarlamak için biraz zaman harcadım.

Çeşitli fikirleri en popüler Python editörlerinde test ettim: PyCharm, VS Code, Jedi tabanlı editörler.

Ich habe mehrere Ideen in den beliebtesten Python-Editoren getestet: PyCharm, VS Code, Jedi-basierte Editoren.

Laut der letzten <a href="https://www.jetbrains.com/research/python-developers-survey-2018/#development-tools" class="external-link" target="_blank">Python-Entwickler-Umfrage</a> deckt das etwa 80 % der Benutzer ab.

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[9] *}

But then we get a `dict` in the parameter `commons` of the *path operation function*.

And we know that editors can't provide a lot of support (like completion) for `dict`s, because they can't know their keys and value types.

We can do better...

## What makes a dependency { #what-makes-a-dependency }

{* ../../docs_src/dependencies/tutorial001_an_py310.py hl[9] *}

Aber dann haben wir ein `dict` im Parameter `commons` der *Pfadoperation-Funktion*.

Und wir wissen, dass Editoren nicht viel Unterstützung (wie etwa Code-Vervollständigung) für `dict`s bieten können, weil sie ihre Schlüssel- und Werttypen nicht kennen.

Das können wir besser machen ...

     <span style="background-color:#007166"><font color="#D3D7CF"> INFO </font></span>  Application startup complete.
```

</div>

Es **ALTAMENTE recomendable** que escribas o copies el código, lo edites y lo ejecutes localmente.

Usarlo en tu editor es lo que realmente te muestra los beneficios de FastAPI, al ver cuán poco código tienes que escribir, todos los chequeos de tipos, autocompletado, etc.

---

## Instalar FastAPI { #install-fastapi }

# EditorConfig helps developers define and maintain consistent
# coding styles between different editors and IDEs
# editorconfig.org

root = true

[*]

indent_style = space
indent_size = 4

end_of_line = lf
charset = utf-8
trim_trailing_whitespace = true
insert_final_newline = true

spelling_languages = en-US

# Markdown files sometimes need trailing whitespaces.
[*.md]
trim_trailing_whitespace = false

            assertTrue(result.modifiedCount() > 0, "Should have removed duplicate dependency");

            // Verify only one dependency remains
            Editor editor = new Editor(document);
            Element root = editor.root();
            Element dependencyManagement = DomUtils.findChildElement(root, "dependencyManagement");