class_docstr: base class of postprocess class
code: def __call__(self, *args, **kwargs):
      return self.call(*args, **kwargs)
  
file_path: delta/delta/utils/postprocess/base_postproc.py
imports: import abc
label_desc: Use image node_id 2 for calling the PostProc obj's underlying member method code with example usage: obj.__call__() and returns: self