code: def from_xmrs(cls, xmrs, **kwargs):
          
          x = cls()
          x.__dict__.update(xmrs.__dict__)
          return x
docs: Facilitate conversion among subclasses.
  
          Args:
              xmrs (:class:`Xmrs`): instance to convert from; possibly
                  an instance of a subclass, such as :class:`Mrs` or
                  :class:`Dmrs`
              **kwargs: additional keyword arguments that may be used
                  by a subclass's redefinition of :meth:`from_xmrs`.