Using a Jupyter notebook:
from dl import storeClient
storeClient.ls(token,'vos://')
If you wanted to ls a certain directory, just append it to the vos:// prefix, e.g.
storeClient.ls(token,'vos://public/') # the final slash is important
Using the Data Lab command line client (after datalab login):
datalab ls
To ls a certain directory (here public):
datalab ls name='public/'