Error cluster-config with Openstack Rocky

[Adrien Fontaine]

I get an error when trying to get a K8s cluster configuration on an Openstack Rocky cloud.

With python-magnumclient 2.11.0 and python 2.7.15 :

magnum cluster-config <cluster_name>

Traceback (most recent call last):
  File "/usr/local/lib/python2.7/site-packages/magnumclient/shell.py", line 640, in main
    OpenStackMagnumShell().main(map(encodeutils.safe_decode, sys.argv[1:]))
  File "/usr/local/lib/python2.7/site-packages/magnumclient/shell.py", line 552, in main
    args.func(self.cs, args)
  File "<decorator-gen-142>", line 2, in do_cluster_config
  File "/usr/local/lib/python2.7/site-packages/magnumclient/common/cliutils.py", line 140, in wrapper
    return func(*args, **kwargs)
  File "/usr/local/lib/python2.7/site-packages/magnumclient/v1/clusters_shell.py", line 288, in do_cluster_config
    cfg_dir=args.dir, force=args.force))
  File "/usr/local/lib/python2.7/site-packages/magnumclient/common/utils.py", line 167, in config_cluster
    force, certs)
  File "/usr/local/lib/python2.7/site-packages/magnumclient/common/utils.py", line 227, in _config_cluster_kubernetes
    if 'csh' in os.environ['SHELL']:
  File "/usr/local/lib/python2.7/UserDict.py", line 40, in __getitem__
    raise KeyError(key)
KeyError: 'SHELL'
ERROR: 'SHELL'

With python-magnumclient 2.11.0 and python 3.7.1 :

magnum cluster-config <cluster_name>

Traceback (most recent call last):
  File "/usr/local/lib/python3.7/site-packages/magnumclient/shell.py", line 640, in main
    OpenStackMagnumShell().main(map(encodeutils.safe_decode, sys.argv[1:]))
  File "/usr/local/lib/python3.7/site-packages/magnumclient/shell.py", line 552, in main
    args.func(self.cs, args)
  File "<decorator-gen-142>", line 2, in do_cluster_config
  File "/usr/local/lib/python3.7/site-packages/magnumclient/common/cliutils.py", line 140, in wrapper
    return func(*args, **kwargs)
  File "/usr/local/lib/python3.7/site-packages/magnumclient/v1/clusters_shell.py", line 288, in do_cluster_config
    cfg_dir=args.dir, force=args.force))
  File "/usr/local/lib/python3.7/site-packages/magnumclient/common/utils.py", line 167, in config_cluster
    force, certs)
  File "/usr/local/lib/python3.7/site-packages/magnumclient/common/utils.py", line 227, in _config_cluster_kubernetes
    if 'csh' in os.environ['SHELL']:
  File "/usr/local/lib/python3.7/os.py", line 678, in __getitem__
    raise KeyError(key) from None
KeyError: 'SHELL'
ERROR: b"'SHELL'"

With python-openstackclient 3.17.0 and python 3.6.4 :

openstack coe cluster config <cluster_name>

a bytes-like object is required, not 'str'
clean_up ConfigCluster: a bytes-like object is required, not 'str'

I can give more information if necessary.