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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def my_application(api):
 """An example application. - Registers a webhook with mbed cloud services - Requests the value of a resource - Prints the value when it arrives """

    device = api.list_connected_devices().first()
    print('using device #', device.id)
    api.delete_device_subscriptions(device.id)

    try:
        print('setting webhook url to:', ngrok_url)
        api.update_webhook(ngrok_url)
        print('requesting resource value for:', resource_path)
        deferred = api.get_resource_value_async(device_id=device.id, resource_path=resource_path)
        print('waiting for async #', deferred.async_id)
        result = deferred.wait(15)
        print('webhook sent us this payload value:', repr(result))
        return result
    except Exception:
        print(traceback.format_exc())
    finally:
        api.delete_webhook()
        print("Deregistered and unsubscribed from all resources. Exiting.")
        exit(1)