The script is available for download from http://gallery.technet.microsoft.com/How-to-create-a-Stored-d01f3fd4. You can also use Microsoft Script Browser for Windows PowerShell ISE to download the sample with one button click from within your scripting environment.
This PowerShell script sample shows how to create a stored access policy for a container in Microsoft Azure.
A stored access policy gives us greater control over shared access signatures we have released. Instead of specifying the signature's lifetime and permissions on the URL, we can specify these parameters within the stored access policy stored on container that is being shared.
You can find more All-In-One Script Framework script samples at https://aka.ms/onescriptingallery