code: def merge(self, src, skip_default=True):
          
          for arg in _arg_names:
              if not hasattr(src, arg):
                  continue
              if getattr(src, arg) is not None or not skip_default:
                  self._merge_opt(arg, src, False)
docs: Merge another set of ``SoSOptions`` into this object.
  
              Merge two ``SoSOptions`` objects by setting unset or default
              values to their value in the ``src`` object.
  
              :param src: the ``SoSOptions`` object to copy from
              :param is_default: ``True`` if new default values are to be set.