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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _cleanup_keys_with_confirmation(self, keys_to_delete):
 """Asks confirmation and then deletes entries with keys. Args: keys_to_delete: list of datastore keys for which entries should be deleted """

    print('Round name: ', self.round_name)
    print('Number of entities to be deleted: ', len(keys_to_delete))
    if not keys_to_delete:
      return
    if self.verbose:
      print('Entities to delete:')
      idx = 0
      prev_key_prefix = None
      dots_printed_after_same_prefix = False
      for k in keys_to_delete:
        if idx >= 20:
          print('   ...')
          print('   ...')
          break
        key_prefix = (k.flat_path[0:1]
                      if k.flat_path[0] in [u'SubmissionType', u'WorkType']
                      else k.flat_path[0])
        if prev_key_prefix == key_prefix:
          if not dots_printed_after_same_prefix:
            print('   ...')
          dots_printed_after_same_prefix = True
        else:
          print('  ', k)
          dots_printed_after_same_prefix = False
          idx += 1
        prev_key_prefix = key_prefix
    print()
    inp = input_str('Are you sure? (type "yes" without quotes to confirm): ')
    if inp != 'yes':
      return
    with self.datastore_client.no_transact_batch() as batch:
      for k in keys_to_delete:
        batch.delete(k)
    print('Data deleted')