if crypto.S3.IsRequested(header) && crypto.SSEC.IsRequested(header) {
		return key, crypto.ErrIncompatibleEncryptionMethod
	}

	k, err := crypto.SSEC.ParseHTTP(header)
	return k[:], err
}

// This function rotates old to new key.
func rotateKey(ctx context.Context, oldKey []byte, newKeyID string, newKey []byte, bucket, object string, metadata map[string]string, cryptoCtx kms.Context) error {
	kind, _ := crypto.IsEncrypted(metadata)

			cleanupFns[i]()
		}
		return nil, PreConditionFailed{}
	}
	return &GetObjectReader{
		ObjInfo:    oi,
		Reader:     r,
		cleanUpFns: cleanupFns,
	}, nil
}

// ObjReaderFn is a function type that takes a reader and returns
// GetObjectReader and an error. Request headers are passed to provide
// encryption parameters. cleanupFns allow cleanup funcs to be
// registered for calling after usage of the reader.

     *            authority.
     * @param tc
     *            The context that should be used to communicate with the named server.
     * @param sids
     *            The SIDs that should be resolved. After this function is called, the names associated with the SIDs
     *            may be queried with the <code>toDisplayString</code>, <code>getDomainName</code>, and <code>getAccountName</code>
     *            methods.
     */

You write standard Python with types:

```Python
from datetime import date

from pydantic import BaseModel

# Declare a variable as a str
# and get editor support inside the function
def main(user_id: str):
    return user_id


# A Pydantic model
class User(BaseModel):
    id: int
    name: str
    joined: date
```

That can then be used like:

```Python

	xhttp "github.com/minio/minio/internal/http"
	xioutil "github.com/minio/minio/internal/ioutil"
	"github.com/minio/pkg/v3/randreader"
)

// SpeedTestResult return value of the speedtest function
type SpeedTestResult struct {
	Endpoint      string
	Uploads       uint64
	Downloads     uint64
	UploadTimes   madmin.TimeDurations
	DownloadTimes madmin.TimeDurations
	DownloadTTFB  madmin.TimeDurations

# Install pacman packages.
RUN C:\tools\msys64\usr\bin\bash.exe -lc \
  'pacman --noconfirm -Syy curl git patch vim unzip zip'

# Install multiple Pythons, but only add one of them to PATH.
RUN function Install-Python { \
        param( \
            [string]$version, \
            [int]$prependPath \
        ) \
        $url = ('https://www.python.org/ftp/python/{0}/python-{0}-amd64.exe' -f $version); \

   * For example, if {@code end = next(next(next(start)))}, then {@code distance(start, end) == 3}
   * and {@code distance(end, start) == -3}. As well, {@code distance(a, a)} is always zero.
   *
   * <p>Note that this function is necessarily well-defined for any discrete type.
   *
   * @return the distance as described above, or {@link Long#MIN_VALUE} or {@link Long#MAX_VALUE} if
   *     the distance is too small or too large, respectively.

 *
 * <p>{@code containsKey(k)}, {@code put(k, v)} and {@code remove(k)} are all (expected and
 * amortized) constant time operations. Expected in the hashtable sense (depends on the hash
 * function doing a good job of distributing the elements to the buckets to a distribution not far
 * from uniform), and amortized since some operations can trigger a hash table resize.
 *

import static org.codelibs.core.stream.StreamUtil.stream;

import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.function.Consumer;
import java.util.stream.Stream;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.codelibs.core.lang.StringUtil;
import org.codelibs.core.misc.Pair;

**FastAPI** 不強制任何特定的意義。

這裡的資訊作為一個指南，而不是要求。

例如，當使用 GraphQL 時，你通常只使用 `POST` 操作。

///

### 第四步：定義 **路徑操作函式**

這是我們的「**路徑操作函式**」：

* **path**: 是 `/`.
* **operation**: 是 `get`.
* **function**: 是裝飾器下面的函式（在 `@app.get("/")` 下面）。

{* ../../docs_src/first_steps/tutorial001.py h1[7] *}

這就是一個 Python 函式。

它將會在 **FastAPI** 收到一個請求時被呼叫，使用 `GET` 操作。

在這種情況下，它是一個 `async` 函式。

---