code: def format_return_annotation(self):
      return _extract_return_annotation(
          str(self), self.has_return_annotation
      )
  
file_path: nnabla/python/src/nnabla/utils/signature_utils.py
imports: import inspect
label_desc: Use image node_id 5 for calling the SignatureEx obj's underlying member method code with example usage: obj.format_return_annotation() and returns: _extract_return_annotation