code: def convert_dotted(params):
          
          if not isinstance(params, dictset):
              params = dictset(params)
  
          dotted_items = {k: v for k, v in params.items() if '.' in k}
  
          if dotted_items:
              dicts = [str2dict(key, val) for key, val in dotted_items.items()]
              dotted = six.functools.reduce(merge_dicts, dicts)
              params = params.subset(['-' + k for k in dotted_items.keys()])
              params.update(dict(dotted))
  
          return params
docs: Convert dotted keys in :params: dictset to a nested dictset.
  
          E.g. {'settings.foo': 'bar'} -> {'settings': {'foo': 'bar'}}