Script Download:
The script is available for download from http://gallery.technet.microsoft.com/Export-a-list-of-users-b0b69c25. 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 script will export shared mailbox full access list in Exchange Online.
You can find more All-In-One Script Framework script samples at http://aka.ms/onescriptingallery