## Dependencies { #dependencies }

FastAPI depends on Pydantic and Starlette.

### `standard` Dependencies { #standard-dependencies }

When you install FastAPI with `pip install "fastapi[standard]"` it comes with the `standard` group of optional dependencies:

Used by Pydantic:

In that case, you can simply swap the standard `dataclasses` with `pydantic.dataclasses`, which is a drop-in replacement:

{* ../../docs_src/dataclasses/tutorial003.py hl[1,5,8:11,14:17,23:25,28] *}

1. We still import `field` from standard `dataclasses`.

2. `pydantic.dataclasses` is a drop-in replacement for `dataclasses`.

<div class="termy">

```console
$ pip install "fastapi[standard]"

---> 100%
```

</div>

/// note

        this.notificationFilter = notificationFilter;
    }

    /**
     * Get the standard lease size for encoding/decoding
     * @return the standard lease context size
     */
    protected int getStandardLeaseSize() {
        // Standard lease V2 size: LeaseKey(16) + LeaseState(4) + Flags(4) + reserved fields
        return 32;
    }

    @Override

For example, to install Uvicorn:

<div class="termy">

```console
$ pip install "uvicorn[standard]"

---> 100%
```

</div>

A similar process would apply to any other ASGI server program.

/// tip

By adding the `standard`, Uvicorn will install and use some recommended extra dependencies.

        * The generated schema will specify that the `set` values are unique (using JSON Schema's `uniqueItems`).
* `bytes`:
    * Standard Python `bytes`.
    * In requests and responses will be treated as `str`.
    * The generated schema will specify that it's a `str` with `binary` "format".
* `Decimal`:
    * Standard Python `Decimal`.
    * In requests and responses, handled the same as a `float`.

## Dependencies { #dependencies }

FastAPI depends on Pydantic and Starlette.

### `standard` Dependencies { #standard-dependencies }

When you install FastAPI with `pip install "fastapi[standard]"` it comes with the `standard` group of optional dependencies:

Used by Pydantic:

By using them, you can take advantage of all these standard-based tools, including these interactive documentation systems.

OpenAPI defines the following security schemes:

* `apiKey`: an application specific key that can come from:
    * A query parameter.
    * A header.
    * A cookie.
* `http`: standard HTTP authentication systems, including:

    }

    @Test
    public void testDecodePartialData() {
        // Create a buffer with only standard lease data (no directory-specific data)
        byte[] buffer = new byte[56]; // Header + name + padding + standard lease data only

        // Write minimal header
        SMBUtil.writeInt4(0, buffer, 0); // Next
        SMBUtil.writeInt2(16, buffer, 4); // NameOffset

	parts3SC := globalStorageClass

	// Object for test case 4 - Standard StorageClass defined as Parity 6, MetaData in PutObject requesting Standard Storage Class
	object4 := "object4"
	metadata4 := make(map[string]string)
	metadata4["x-amz-storage-class"] = storageclass.STANDARD
	globalStorageClass.Update(storageclass.Config{
		Standard: storageclass.StorageClass{
			Parity: 6,
		},
	})