class_docstr: Sample negative class center
      
class_docstr_tok: ["Sample","negative","class","center"]
docstr: Return:
  -------
  negative_center_index: list of int
docstr_tok: ["Return",":","--","--","--","-","negative_center_index",":","list","of","int"]
code: def __call__(self, positive_center_index):
      """
      Return:
      -------
      negative_center_index: list of int
      """
      negative_class_pool = np.setdiff1d(
          self.negative_class_pool, positive_center_index
      )
      negative_sample_size = self.num_sample - len(
          positive_center_index
      )
      negative_center_index = np.random.choice(
          negative_class_pool, negative_sample_size, replace=False
      )
      return negative_center_index
  
file_path: insightface/recognition/partial_fc/mxnet/memory_samplers.py
imports: import numpy
label_desc: Use image node_id 2 for calling the CenterNegetiveClassSample obj's underlying member method code with example usage: obj.__call__(positive_center_index) and returns: negative_center_index