```

In this case, `item_id` is declared to be an `int`.

!!! check
    This will give you editor support inside of your function, with error checks, completion, etc.

## Data <abbr title="also known as: serialization, parsing, marshalling">conversion</abbr>

"docs_src/dependencies/tutorial008b.py" = ["B904"]
"docs_src/dependencies/tutorial008b_an.py" = ["B904"]
"docs_src/dependencies/tutorial008b_an_py39.py" = ["B904"]


[tool.ruff.lint.isort]
known-third-party = ["fastapi", "pydantic", "starlette"]

[tool.ruff.lint.pyupgrade]
# Preserve types, even if a file imports `from __future__ import annotations`.

* <a href="https://github.com/OAI/OpenAPI-Specification" class="external-link" target="_blank"><strong>OpenAPI</strong></a> for API creation, including declarations of <abbr title="also known as: endpoints, routes">path</abbr> <abbr title="also known as HTTP methods, as POST, GET, PUT, DELETE">operations</abbr>, parameters, body requests, security, etc.

**FastAPI** 🤝 👆 📄:

### ⚓️ 🔛 📂 🐩

* <a href="https://github.com/OAI/OpenAPI-Specification" class="external-link" target="_blank"><strong>🗄</strong></a> 🛠️ 🏗, ✅ 📄 <abbr title="also known as: endpoints, routes">➡</abbr> <abbr title="also known as HTTP methods, as POST, GET, PUT, DELETE">🛠️</abbr>, 🔢, 💪 📨, 💂‍♂, ♒️.
* 🏧 📊 🏷 🧾 ⏮️ <a href="https://json-schema.org/" class="external-link" target="_blank"><strong>🎻 🔗</strong></a> (🗄 ⚫️ 🧢 🔛 🎻 🔗).

Pass `*`, as the first parameter of the function.

Python won't do anything with that `*`, but it will know that all the following parameters should be called as keyword arguments (key-value pairs), also known as <abbr title="From: K-ey W-ord Arg-uments"><code>kwargs</code></abbr>. Even if they don't have a default value.

```Python hl_lines="7"
{!../../../docs_src/path_params_numeric_validations/tutorial003.py!}
```

```Python hl_lines="7"
{!../../../docs_src/path_params/tutorial002.py!}
```

👉 💼, `item_id` 📣 `int`.

!!! check
    👉 🔜 🤝 👆 👨‍🎨 🐕‍🦺 🔘 👆 🔢, ⏮️ ❌ ✅, 🛠️, ♒️.

## 💽 <abbr title="also known as: serialization, parsing, marshalling">🛠️</abbr>

🚥 👆 🏃 👉 🖼 &amp; 📂 👆 🖥 <a href="http://127.0.0.1:8000/items/3" class="external-link" target="_blank">http://127.0.0.1:8000/items/3</a>, 👆 🔜 👀 📨:

```JSON

This means that you can send only the data that you want to update, leaving the rest intact.

!!! note
    `PATCH` is less commonly used and known than `PUT`.

    And many teams use only `PUT`, even for partial updates.

    You are **free** to use them however you want, **FastAPI** doesn't impose any restrictions.