code: def format_argument_signature(self):
      return _extract_argument_signature(str(self))
  
file_path: nnabla/python/src/nnabla/utils/signature_utils.py
imports: import inspect
label_desc: Use image node_id 4 for calling the SignatureEx obj's underlying member method code with example usage: obj.format_argument_signature() and returns: _extract_argument_signature