code: def DedupVcardFilenames(vcard_dict):
      
      remove_keys = []
      add_pairs = []
      for k, v in vcard_dict.items():
          if not len(v) > 1:
              continue
          for idx, vcard in enumerate(v):
              fname, ext = os.path.splitext(k)
              fname = '{}-{}'.format(fname, idx + 1)
              fname = fname + ext
              assert fname not in vcard_dict
              add_pairs.append((fname, vcard))
          remove_keys.append(k)
  
      for k, v in add_pairs:
          vcard_dict[k].append(v)
  
      for k in remove_keys:
          vcard_dict.pop(k)
  
      return vcard_dict
docs: Make sure every vCard in the dictionary has a unique filename.