class_docstr: abstract of Frontend 
code: def __init__(self, config):
      raise NotImplementedError()
  
file_path: delta/delta/data/frontend/base_frontend.py
imports: import abc
  import delta.compat
  from delta.utils.hparam import HParams
label_desc: Use image node_id 1 to create a new ABCFrontend object  with example: obj = ABCFrontend(config)