old_contents: #!/usr/bin/env python
  
  # --------------------------------------------------------------------------------------------
  # Copyright (c) Microsoft Corporation. All rights reserved.
  # Licensed under the MIT License. See License.txt in the project root for license information.
  # --------------------------------------------------------------------------------------------
  
  """
  Example to demonstrate utilizing AzureNamedKeyCredential to authenticate with Event Hubs asynchronously.
  """
  
  # pylint: disable=C0111
  
  import os
  import asyncio
  import time
  from azure.core.credentials import AzureNamedKeyCredential
  from azure.eventhub.aio import EventHubProducerClient
  from azure.eventhub import EventData
  
  # Target namespace and hub must also be specified.
  FULLY_QUALIFIED_NAMESPACE = os.environ['EVENT_HUB_HOSTNAME']
  EVENTHUB_NAME = os.environ['EVENT_HUB_NAME']
  
  EVENTHUB_POLICY_NAME = os.environ['EVENT_HUB_SAS_POLICY']
  EVENTHUB_KEY = os.environ['EVENT_HUB_SAS_KEY']
  
  credential = AzureNamedKeyCredential(EVENTHUB_POLICY_NAME, EVENTHUB_KEY)
  
  producer_client = EventHubProducerClient(
      fully_qualified_namespace=FULLY_QUALIFIED_NAMESPACE,
      eventhub_name=EVENTHUB_NAME,
      credential=credential,
      logging_enable=True
  )
  
  start_time = time.time()
  async def authenticate_with_named_key():
      async with producer_client:
          event_data_batch = await producer_client.create_batch()
          event_data_batch.add(EventData('Single message'))
          await producer_client.send_batch(event_data_batch)
  
  loop = asyncio.get_event_loop()
  start_time = time.time()
  loop.run_until_complete(authenticate_with_named_key())
  print("Send messages in {} seconds.".format(time.time() - start_time))
  
new_contents: #!/usr/bin/env python
  
  # --------------------------------------------------------------------------------------------
  # Copyright (c) Microsoft Corporation. All rights reserved.
  # Licensed under the MIT License. See License.txt in the project root for license information.
  # --------------------------------------------------------------------------------------------
  
  """
  Example to demonstrate utilizing AzureNamedKeyCredential to authenticate with Event Hubs asynchronously.
  """
  
  # pylint: disable=C0111
  
  import os
  import asyncio
  import time
  from azure.core.credentials import AzureNamedKeyCredential
  from azure.eventhub.aio import EventHubProducerClient
  from azure.eventhub import EventData
  
  # Target namespace and hub must also be specified.
  FULLY_QUALIFIED_NAMESPACE = os.environ['EVENT_HUB_HOSTNAME']
  EVENTHUB_NAME = os.environ['EVENT_HUB_NAME']
  
  EVENTHUB_POLICY_NAME = os.environ['EVENT_HUB_SAS_POLICY']
  EVENTHUB_KEY = os.environ['EVENT_HUB_SAS_KEY']
  
  credential = AzureNamedKeyCredential(EVENTHUB_POLICY_NAME, EVENTHUB_KEY)
  
  producer_client = EventHubProducerClient(
      fully_qualified_namespace=FULLY_QUALIFIED_NAMESPACE,
      eventhub_name=EVENTHUB_NAME,
      credential=credential,
      logging_enable=True
  )
  
  start_time = time.time()
  async def authenticate_with_named_key():
      async with producer_client:
          event_data_batch = await producer_client.create_batch()
          event_data_batch.add(EventData('Single message'))
          await producer_client.send_batch(event_data_batch)
  
  start_time = time.time()
  asyncio.run(authenticate_with_named_key())
  print("Send messages in {} seconds.".format(time.time() - start_time))
  
subject: Update async legacy module to newer async module in authenticate_with_azure_named_key_credential_async.py (#21755)