code: def _group_pixels(self, center_points, offsets, sem_seg):
      height, width = offsets.shape[1:]
  
      # Generates a coordinate map, where each location is the coordinate of that location.
      y_coord, x_coord = paddle.meshgrid(
          paddle.arange(height, dtype=offsets.dtype),
          paddle.arange(width, dtype=offsets.dtype),
      )
      coord = paddle.concat(
          (y_coord.unsqueeze(0), x_coord.unsqueeze(0)), axis=0
      )
  
      center_loc = coord + offsets
      center_loc = center_loc.flatten(1).T.unsqueeze_(0)  # [1, H*W, 2]
  
      center_points = center_points.unsqueeze(1)
      distance = paddle.norm(
          (center_points - center_loc).astype("float32"), axis=-1
      )
      instance_id = (
          paddle.argmin(distance, axis=0).reshape((1, height, width))
          + 1
      )
  
      return instance_id
  
file_path: PaddleSeg/contrib/PanopticSeg/paddlepanseg/postprocessors/panoptic_deeplab_pp.py
imports: from collections import Counter
  import paddle
  import paddle.nn.functional
  from paddlepanseg.cvlibs import build_info_dict, manager
  from paddlepanseg.utils import encode_pan_id
  from paddlepanseg.postprocessors.base_pp import Postprocessor
label_desc: Use image node_id 4 for calling the PanopticDeepLabPostprocessor obj's underlying member method code with example usage: obj._group_pixels(center_points, offsets, sem_seg) and returns: instance_id