- For volumes that allow attaches across multiple nodes, attach and detach operations across different nodes are now executed in parallel. ([#89239](https://github.com/kubernetes/kubernetes/pull/89239), [@verult](...

# Header Parameter Models { #header-parameter-models }

If you have a group of related **header parameters**, you can create a **Pydantic model** to declare them.

This would allow you to **re-use the model** in **multiple places** and also to declare validations and metadata for all the parameters at once. 😎

/// note

This is supported since FastAPI version `0.115.0`. 🤓

///

# Additional Status Codes { #additional-status-codes }

By default, **FastAPI** will return the responses using a `JSONResponse`, putting the content you return from your *path operation* inside of that `JSONResponse`.

It will use the default status code or the one you set in your *path operation*.

## Additional status codes { #additional-status-codes_1 }

# Form Models { #form-models }

You can use **Pydantic models** to declare **form fields** in FastAPI.

/// info

To use forms, first install <a href="https://github.com/Kludex/python-multipart" class="external-link" target="_blank">`python-multipart`</a>.

Make sure you create a [virtual environment](../virtual-environments.md){.internal-link target=_blank}, activate it, and then install it, for example:

```console
$ pip install python-multipart
```

## Nested Models { #nested-models }

Each attribute of a Pydantic model has a type.

But that type can itself be another Pydantic model.

So, you can declare deeply nested JSON "objects" with specific attribute names, types and validations.

All that, arbitrarily nested.

### Define a submodel { #define-a-submodel }

For example, we can define an `Image` model:

/// note | Нотатки

Ця можливість підтримується починаючи з версії FastAPI `0.115.0`. 🤓

///

## Параметри Заголовків з Використанням Pydantic Model

Оголосіть потрібні **параметри заголовків** у **Pydantic моделі**, а потім оголосіть параметр як `Header`:

{* ../../docs_src/header_param_models/tutorial001_an_py310.py hl[9:14,18] *}

	Active    bool
}

type Account struct {
	gorm.Model
	UserID sql.NullInt64
	Number string
}

type Pet struct {
	gorm.Model
	UserID *uint
	Name   string
	Toy    Toy `gorm:"polymorphic:Owner;"`
}

type Toy struct {
	gorm.Model
	Name      string
	OwnerID   string
	OwnerType string
}

type Tools struct {
	gorm.Model
	Name     string
	CustomID string
	Type     string
}

# OpenAPI `models`

OpenAPI Pydantic models used to generate and validate the generated OpenAPI.

    * or grant self-deletion permission explicitly:
        * `kubectl create clusterrole self-deleting-nodes --verb=delete --resource=nodes`
        * `kubectl create clusterrolebinding self-deleting-nodes --clusterrole=self-deleting-nodes --group=system:nodes`

    * Change eviction policies in NodeController:
      *  add a "partialDisruption" mode, when more than 33% of Nodes in the zone are not Ready
      *  add "fullDisruption" mode, when all Nodes in the zone are not Ready
    * Eviction behavior depends on the mode in which NodeController is operating: