Merge pull request #261719 from pauljewellmsft/py-async

Add async sample for Python access tier article

Author: v-dirichards

articles/storage/blobs/storage-blob-use-access-tier-python.md

@@ -8,7 +8,7 @@ ms.author: pauljewell
 
 ms.service: azure-blob-storage
 ms.topic: how-to
-ms.date: 08/02/2023
+ms.date: 12/20/2023
 ms.devlang: python
 ms.custom: devx-track-python, devguide-python
 ---
@@ -17,7 +17,9 @@ ms.custom: devx-track-python, devguide-python
 
 [!INCLUDE [storage-dev-guide-selector-access-tier](../../../includes/storage-dev-guides/storage-dev-guide-selector-access-tier.md)]
 
-This article shows how to set or change the access tier for a block blob using the [Azure Storage client library for Python](/python/api/overview/azure/storage). 
+This article shows how to set or change the access tier for a block blob using the [Azure Storage client library for Python](/python/api/overview/azure/storage).
+
+To learn about changing a blob's access tier using asynchronous APIs, see [Change a blob's access tier asynchronously](#change-a-blobs-access-tier-asynchronously).
 
 ## Prerequisites
 
@@ -62,6 +64,37 @@ The following code example shows how to rehydrate an archived blob to the `Hot`
 
 To learn more about copying a blob with Python, see [Copy a blob with Python](storage-blob-copy-python.md).
 
+## Change a blob's access tier asynchronously
+
+The Azure Blob Storage client library for Python supports changing a blob's access tier asynchronously. To learn more about project setup requirements, see [Asynchronous programming](storage-blob-python-get-started.md#asynchronous-programming).
+
+Follow these steps to change a blob's access tier using asynchronous APIs:
+
+1. Add the following import statements:
+
+    ```python
+    import asyncio
+
+    from azure.storage.blob import (
+    StandardBlobTier
+    )
+    from azure.identity.aio import DefaultAzureCredential
+    from azure.storage.blob.aio import (
+    BlobServiceClient,
+    BlobClient
+    )
+    ```
+
+1. Add code to run the program using `asyncio.run`. This function runs the passed coroutine, `main()` in our example, and manages the `asyncio` event loop. Coroutines are declared with the async/await syntax. In this example, the `main()` coroutine first creates the top level `BlobServiceClient` using `async with`, then calls the method that changes the blob's access tier. Note that only the top level client needs to use `async with`, as other clients created from it share the same connection pool.
+
+    :::code language="python" source="~/azure-storage-snippets/blobs/howto/python/blob-devguide-py/blob_devguide_access_tiers_async.py" id="Snippet_create_client_async":::
+
+1. Add code to change the blob's access tier. The code is the same as the synchronous example, except that the method is declared with the `async` keyword and the `await` keyword is used when calling the `set_standard_blob_tier` method.
+
+    :::code language="python" source="~/azure-storage-snippets/blobs/howto/python/blob-devguide-py/blob_devguide_access_tiers_async.py" id="Snippet_change_blob_access_tier":::
+
+With this basic setup in place, you can implement other examples in this article as coroutines using async/await syntax.
+
 ## Resources
 
 To learn more about setting access tiers using the Azure Blob Storage client library for Python, see the following resources.
@@ -76,7 +109,7 @@ The Azure SDK for Python contains libraries that build on top of the Azure REST
 
 ### Code samples
 
-- [View code samples from this article (GitHub)](https://github.com/Azure-Samples/AzureStorageSnippets/blob/master/blobs/howto/python/blob-devguide-py/blob_devguide_access_tiers.py)
+- View [synchronous](https://github.com/Azure-Samples/AzureStorageSnippets/blob/master/blobs/howto/python/blob-devguide-py/blob_devguide_access_tiers.py) or [asynchronous](https://github.com/Azure-Samples/AzureStorageSnippets/blob/master/blobs/howto/python/blob-devguide-py/blob_devguide_access_tiers_async.py) code samples from this article (GitHub)
 
 ### See also