code: def decorate_method(wrapped):
      
      def wrapper(self):
          lines = Lines()
          if hasattr(self.model, wrapped.__name__):
              print('            . %s' % wrapped.__name__)
              lines.add(1, method_header(wrapped.__name__, nogil=True))
              for line in wrapped(self):
                  lines.add(2, line)
          return lines
      functools.update_wrapper(wrapper, wrapped)
      wrapper.__doc__ = 'Lines of model method %s.' % wrapped.__name__
      return property(wrapper)
docs: The decorated method will return a |Lines| object including
      a method header.  However, the |Lines| object will be empty if
      the respective model does not implement a method with the same
      name as the wrapped method.