'Set up the storage system for file-based sessions.
This should only be called once per process; this will be done
automatically when using sessions.init (as the built-in Tool does).'

def setup(cls, **kwargs):

    kwargs['storage_path'] = os.path.abspath(kwargs['storage_path'])
    for (k, v) in kwargs.items():
        setattr(cls, k, v)
