code: def test_apply_more_proc(self):
      def func(x):
          print("x")
          logger.info("demo")
          return len(x)
  
      data = DataSet(
          {
              "x": ["xxxxas1w xw zxw xz", "xxxxas1w xw zxw xz"] * 100,
              "y": [0, 1] * 100,
          }
      )
      data.apply_field(
          func, field_name="x", new_field_name="len_x", num_proc=2
      )
  
imports: import os
  import pytest
  import numpy
  from fastNLP.core.dataset import DataSet, FieldArray, Instance, ApplyResultException
  from fastNLP import logger
label_desc: Use image node_id 33 for calling the TestDataSetMethods obj's underlying member method code with example usage: obj.test_apply_more_proc() and returns: len