Traceback (most recent call last):
  File "/dist-packages/trytond/protocols/jsonrpc.py", line 108, in _marshaled_dispatch
    response['result'] = dispatch_method(method, params)
  File "/dist-packages/trytond/protocols/jsonrpc.py", line 147, in _dispatch
    res = dispatch(*args)
  File "/dist-packages/trytond/protocols/dispatcher.py", line 39, in dispatch
    res = security.login(database_name, user, session)
  File "/dist-packages/trytond/security.py", line 23, in login
    user_obj = pool.get('res.user')
  File "/dist-packages/trytond/pool.py", line 135, in get
    return self._pool[self.database_name][type][name]
KeyError: 'res.user'