title: list virtual folders in azure blob storage via python API
body: <p>I was reading <a href="https://azure.microsoft.com/en-us/documentation/articles/storage-python-how-to-use-blob-storage/" rel="noreferrer">this tutorial</a> but I cannot find a way to list all the (virtual) folder under a container without getting all the files. I have 26K files in 500 (virtual) folders. I just want to get the list of folder without having to wait few minutes to get the output of <code>list_blobs</code> containing the entire file list. Is there a way to do that? or at least tell <code>list_blobs</code> to not go deeper than <code>n</code> levels below a container?</p>