code: def test_pretraining_default():
      """Test that pretraining defaults to a character objective"""
      config = Config().from_str(pretrain_string_internal)
      nlp = util.load_model_from_config(
          config, auto_fill=True, validate=False
      )
      filled = nlp.config
      pretrain_config = util.load_config(DEFAULT_CONFIG_PRETRAIN_PATH)
      filled = pretrain_config.merge(filled)
      assert (
          "PretrainCharacters"
          in filled["pretraining"]["objective"]["@architectures"]
      )
  
imports: from pathlib import Path
  import numpy
  import pytest
  import srsly
  from thinc.api import Config, get_current_ops
  from spacy import util
  from spacy.lang.en import English
  from spacy.language import DEFAULT_CONFIG_PATH, DEFAULT_CONFIG_PRETRAIN_PATH
  from spacy.ml.models.multi_task import create_pretrain_vectors
  from spacy.tokens import Doc, DocBin
  from spacy.training.initialize import init_nlp
  from spacy.training.loop import train
  from spacy.training.pretrain import pretrain
  from spacy.vectors import Vectors
  from spacy.vocab import Vocab
  from ..util import make_tempdir
label_desc: Use image node_id 1 for calling a global function with example usage: test_pretraining_default() without return types