def __init__(self, groups=None):
        super(GroupedRequirements, self).__init__(NamedRequirements)
        self.groups = groups or self.default_groups
        self.filename = None
        self.create_default_groups()
def items(self, section_name):
            if section_name != section:
                raise NoSectionError(section_name)
            return {
                'memcache_servers': memcache_servers,
                'memcache_serialization_support':
                memcache_serialization_support,
                'memcache_max_connections': memcache_max_connections,
            }