Invalid command:'token' on "otc s3 ls" command

[make-ing]

i just installed the python-otcclient via pip did the configuration via otc --configure but then i tried to issue the otc s3 ls command which failed with the message:

Invalid command:'token'
usage: otc [-h] [-V] [-d] [--configure [{user,proxy}]] <plugin name> <command>
Available plugin commands:
('rds', ['describe_db_instances', 'describe_datastore', 'describe_flavors'])
...```
any suggestions on how to solve this problem?