class_docstr: abstract class
class_docstr_tok: ["abstract","class"]
docstr: dataset meta data
docstr_tok: ["dataset","meta","data"]
code: def feature_spec(self):
      """dataset meta data"""
      raise NotImplementedError()
  
file_path: delta/delta/data/task/base_task.py
imports: import abc
label_desc: Use image node_id 4 for calling the Task obj's underlying member method code with example usage: obj.feature_spec() without return types