human
I wrote the below code

    _unicode = defaults.pop('_unicode', False)
    to_unicode = safeunicode
    if ((_unicode is not False) and hasattr(_unicode, '__call__')):
        to_unicode = _unicode
    def unicodify(s):
        if (_unicode and isinstance(s, str)):
            return to_unicode(s)
        else:
            return s
    def getvalue(x):
        if (hasattr(x, 'file') and hasattr(x, 'value')):
            return x.value
        elif hasattr(x, 'value'):
            return unicodify(x.value)
        else:
            return unicodify(x)
    stor = Storage()
    for key in (requireds + tuple(mapping.keys())):
        value = mapping[key]
        if isinstance(value, list):
            if isinstance(defaults.get(key), list):
                value = [getvalue(x) for x in value]
            else:
                value = value[(-1)]
        if (not isinstance(defaults.get(key), dict)):
            value = getvalue(value)
        if (isinstance(defaults.get(key), list) and (not isinstance(value, list))):
            value = [value]
        setattr(stor, key, value)
    for (key, value) in iteritems(defaults):
        result = value
        if hasattr(stor, key):
            result = stor[key]
        if ((value == ()) and (not isinstance(result, tuple))):
            result = (result,)
        setattr(stor, key, result)
    return stor

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

def storify(mapping, *requireds, **defaults):