code: def __call__(self, model):
      paddleslim = try_import("paddleslim")
      self.ptq = paddleslim.PTQ(**self.ptq_config)
      model.eval()
      quant_model = self.ptq.quantize(
          model, fuse=self.fuse, fuse_list=self.fuse_list
      )
  
      return quant_model
  
file_path: PaddleDetection/ppdet/slim/quant.py
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  from paddle.utils import try_import
  from ppdet.core.workspace import register, serializable
  from ppdet.utils.logger import setup_logger
label_desc: Use image node_id 2 for calling the PTQ obj's underlying member method code with example usage: obj.__call__(model) and returns: quant_model