code: def _drop_empty_instance(data_bundle, field_name):
      r"""
      删除data_bundle的DataSet中存在的某个field为空的情况
  
      :param ~fastNLP.DataBundle data_bundle:
      :param str field_name: 对哪个field进行检查，如果为None，则任意field为空都会删掉
      :return: 传入的DataBundle
      """
  
      def empty_instance(ins):
          if field_name:
              field_value = ins[field_name]
              if field_value in ((), {}, [], ""):
                  return True
              return False
          for _, field_value in ins.items():
              if field_value in ((), {}, [], ""):
                  return True
          return False
  
      for name, dataset in data_bundle.datasets.items():
          dataset.drop(empty_instance)
  
      return data_bundle
  
file_path: fastNLP/fastNLP/io/pipe/utils.py
imports: from typing import List
  from ...core.vocabulary import Vocabulary
  from fastNLP.core.log import logger
  from pkg_resources import parse_version
label_desc: Use image node_id 9 for calling a global function with example usage: _drop_empty_instance(data_bundle, field_name) and returns: data_bundle, False, False, True, True