code: def kmeans_maximizations(self, whs, centers, assignments):
      new_centers = np.zeros_like(centers)
      for i in range(centers.shape[0]):
          mask = assignments == i
          if mask.sum():
              new_centers[i, :] = whs[mask].mean(0)
      return new_centers
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import os
  import sys
  from ppdet.utils.logger import setup_logger
  from scipy.cluster.vq import kmeans
  import numpy
  from tqdm import tqdm
  from ppdet.utils.cli import ArgsParser
  from ppdet.utils.check import check_gpu, check_version, check_config
  from ppdet.core.workspace import load_config, merge_config
label_desc: Use image node_id 5 for calling the YOLOv2AnchorCluster obj's underlying member method code with example usage: obj.kmeans_maximizations(whs, centers, assignments) and returns: new_centers