code: def __str__(self):
      return f"KalmanFilter(dim_x={self.dim_x})"
  
file_path: darts/darts/models/filtering/kalman_filter.py
imports: from abc import ABC
  from copy import deepcopy
  from typing import Optional
  import numpy
  import pandas
  from nfoursid.kalman import Kalman
  from nfoursid.nfoursid import NFourSID
  from darts.logging import raise_if, raise_if_not
  from darts.models.filtering.filtering_model import FilteringModel
  from darts.timeseries import TimeSeries
label_desc: Use image node_id 2 for calling the KalmanFilter obj's underlying member method code with example usage: obj.__str__() and returns: str, self, str