Return a new environ dict targeting the given wsgi.version

def get_environ(self):
        """Return a new environ dict targeting the given wsgi.version"""
        req = self.req
        env_10 = WSGIGateway_10.get_environ(self)
        env = dict([(k.decode('ISO-8859-1'), v) for k, v in env_10.iteritems()])
        env[u'wsgi.version'] = ('u', 0)
        
        # Request-URI
        env.setdefault(u'wsgi.url_encoding', u'utf-8')
        try:
            for key in [u"PATH_INFO", u"SCRIPT_NAME", u"QUERY_STRING"]:
                env[key] = env_10[str(key)].decode(env[u'wsgi.url_encoding'])
        except UnicodeDecodeError:
            # Fall back to latin 1 so apps can transcode if needed.
            env[u'wsgi.url_encoding'] = u'ISO-8859-1'
            for key in [u"PATH_INFO", u"SCRIPT_NAME", u"QUERY_STRING"]:
                env[key] = env_10[str(key)].decode(env[u'wsgi.url_encoding'])
        
        for k, v in sorted(env.items()):
            if isinstance(v, str) and k not in ('REQUEST_URI', 'wsgi.input'):
                env[k] = v.decode('ISO-8859-1')
        
        return env