Since OC 8 it is possible to tag files (arbitrary tags or favorites).
pyocclient should be extended with functions to get/set tags from files.
To read tags from files: the PROPFIND needs to explicitly request the "oc:tags" and "oc:favorite" fields.
I suggest to add an extra optional keyword argument "include_fields = tags" to the "list" functions.
To set tags on files, need to use PROPPATCH and pass the appropriate "oc:tags" and "oc:favorite" elements.