human
Here's a good function header given the following:
I wrote the below code

    @property
    def prompt(self):
        try:
            powerline = self.powerline
        except AttributeError:
            powerline = PDBPowerline()
            powerline.setup(self)
            self.powerline = powerline
        return PowerlineRenderResult(powerline.render(side=u'left'))
    @prompt.setter
    def prompt(self, _):
        pass
    @prompt.deleter
    def prompt(self):
        pass
    if (not hasattr(cls, u'__class__')):
        old_cls = cls
        class cls(cls, object, ):
            __module__ = cls.__module__
            __doc__ = cls.__doc__
        cls.__name__ = old_cls.__name__
    cls.prompt = prompt
    return cls

What's a good function header?
assistant
#Here's a good function header.

def use_powerline_prompt(cls):