code: def _read_filter(fid):
      """Read filter information."""
      f = dict()
      f["freq"] = _read_double(fid)[0]
      f["class"] = _read_int(fid)
      f["type"] = _read_int(fid)
      f["npar"] = _read_int2(fid)
      f["pars"] = _read_double(fid, f["npar"])
      return f
  
file_path: mne-python/mne/io/ctf/res4.py
imports: import os.path
  import numpy
  from ...utils import logger
  from .constants import CTF
label_desc: Use image node_id 8 for calling a global function with example usage: _read_filter(fid) and returns: f