code: def prepare(self, ctx_id, **kwargs):
      if ctx_id < 0:
          self.session.set_providers(["CPUExecutionProvider"])
      nms_thresh = kwargs.get("nms_thresh", None)
      if nms_thresh is not None:
          self.nms_thresh = nms_thresh
      det_thresh = kwargs.get("det_thresh", None)
      if det_thresh is not None:
          self.det_thresh = det_thresh
      input_size = kwargs.get("input_size", None)
      if input_size is not None:
          if self.input_size is not None:
              print(
                  "warning: det_size is already set in detection model, ignore"
              )
          else:
              self.input_size = input_size
  
file_path: insightface/python-package/insightface/model_zoo/retinaface.py
imports: from __future__ import division
  import datetime
  import numpy
  import onnx
  import onnxruntime
  import os
  import os.path
  import cv2
  import sys
label_desc: Use image node_id 3 for calling the RetinaFace obj's underlying member method code with example usage: obj.prepare(ctx_id) without return types