<s> from __future__ import ( absolute_import , division , generators , nested_scopes , print_function , <EOL> unicode_literals , with_statement ) <EOL> from abc import ABCMeta <EOL> class SingletonMetaclass ( type ) : <EOL> """<STR_LIT>""" <EOL> def __call__ ( cls , * args , ** kwargs ) : <EOL> if not hasattr ( cls , '<STR_LIT>' ) : <EOL> cls . instance = super ( SingletonMetaclass , cls ) . __call__ ( * args , ** kwargs ) <EOL> return cls . instance <EOL> Singleton = SingletonMetaclass ( str ( '<STR_LIT>' ) , ( object , ) , { } ) <EOL> AbstractClass = ABCMeta ( str ( '<STR_LIT>' ) , ( object , ) , { } ) </s>
