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

    cache_attr_name = (u'_%s' % f.__name__)
    docstring = f.__doc__
    def get_prop_value(obj):
        try:
            return getattr(obj, cache_attr_name)
        except AttributeError:
            value = f(obj)
            setattr(obj, cache_attr_name, value)
            return value
    return property(get_prop_value, doc=docstring)

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

def lazyproperty(f):