human
I wrote the below code

    def _dec(*args, **kwargs):
        if args:
            args = list(args)
            args[0] = force_text(args[0])
            if (isinstance(args[0], SafeData) and getattr(_dec._decorated_function, u'is_safe', False)):
                return mark_safe(func(*args, **kwargs))
        return func(*args, **kwargs)
    _dec._decorated_function = getattr(func, u'_decorated_function', func)
    for attr in (u'is_safe', u'needs_autoescape'):
        if hasattr(func, attr):
            import warnings
            warnings.warn((u'Setting    the    %s    attribute    of    a    template    filter    function    is    deprecated.
   use    @register.filter(%s=%s)    instead' % (attr, attr, getattr(func, attr))), DeprecationWarning)
            setattr(_dec, attr, getattr(func, attr))
    return wraps(func)(_dec)

What's a good function header?

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

def stringfilter(func):