code: def remove_singletons_clusters(self, debug=False):
      for doc_idx in range(len(self.docs)):
          remove_id = []
          kept = False
          for key, mentions in self.clusters[doc_idx].items():
              if len(mentions) == 1:
                  remove_id.append(key)
                  self.mention_to_cluster[doc_idx][key] = None
              else:
                  kept = True
                  if debug:
                      l = list(
                          self.m_loc[doc_idx][m][3] for m in mentions
                      )
                      print("Cluster found", key)
                      print(
                          "Corefs:",
                          "|".join(
                              str(self.docs[doc_idx]["mentions"][m_idx])
                              + " ("
                              + str(m_idx)
                              + ")"
                              for m_idx in l
                          ),
                      )
          if not kept and debug:
              print("❄️ No coreference found")
          for rem in remove_id:
              del self.clusters[doc_idx][rem]
  
imports: import os
  import subprocess
  import io
  import pickle
  import torch
  from torch.utils.data import DataLoader
  from neuralcoref.train.conllparser import FEATURES_NAMES
  from neuralcoref.train.dataset import NCBatchSampler, padder_collate
  from neuralcoref.train.compat import unicode_
label_desc: Use image node_id 5 for calling the ConllEvaluator obj's underlying member method code with example usage: obj.remove_singletons_clusters(debug) without return types