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

    def _dec(*args, **kwargs):
        if args:
            args = list(args)
            args[0] = force_unicode(args[0])
            if (isinstance(args[0], SafeData) and getattr(func, 'is_safe', False)):
                return mark_safe(func(*args, **kwargs))
        return func(*args, **kwargs)
    _dec._decorated_function = getattr(func, '_decorated_function', func)
    for attr in ('is_safe', 'needs_autoescape'):
        if hasattr(func, attr):
            setattr(_dec, attr, getattr(func, attr))
    return wraps(func)(_dec)

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

def stringfilter(func):