bad-element error with netconf filter

[HeikkiLavaste]

Hi.

If I connect to one of the sandbox XE devices, the filter works fine. (dne-dna-code/intro-mdp/netconf/get_interface_list.py)
If I connect to CSR running locally (XE 17.03.02), I get following error.

Sending a operation to the device.

Traceback (most recent call last):
File "get_interface_list.py", line 65, in
netconf_reply = m.get_config(source = 'running', filter=netconf_filter)
File "/home/heikki/.local/lib/python3.8/site-packages/ncclient/manager.py", line 212, in execute
return cls(self._session,
File "/home/heikki/.local/lib/python3.8/site-packages/ncclient/operations/retrieve.py", line 166, in request
return self._request(node)
File "/home/heikki/.local/lib/python3.8/site-packages/ncclient/operations/rpc.py", line 341, in _request
raise self._reply.error
ncclient.operations.rpc.RPCError: {'type': 'protocol', 'tag': 'unknown-element', 'severity': 'error', 'info': 'filter\n\n', 'path': '\n /rpc/get-config\n ', 'message': None}

If I remove filter, ncclient runs without errors.
I'm guessing I'm doing something very simple, very wrong. If somebody can tell me what it is, much appreciated.

Br,
Heikki