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# This file is dual licensed under the terms of the Apache License, Version 

# 2.0, and the BSD License. See the LICENSE file in the root of this repository 

# for complete details. 

from __future__ import absolute_import, division, print_function 

 

import sys 

 

 

PY2 = sys.version_info[0] == 2 

PY3 = sys.version_info[0] == 3 

 

# flake8: noqa 

 

if PY3: 

string_types = str, 

else: 

string_types = basestring, 

 

 

def with_metaclass(meta, *bases): 

""" 

Create a base class with a metaclass. 

""" 

# This requires a bit of explanation: the basic idea is to make a dummy 

# metaclass for one level of class instantiation that replaces itself with 

# the actual metaclass. 

class metaclass(meta): 

def __new__(cls, name, this_bases, d): 

return meta(name, bases, d) 

return type.__new__(metaclass, 'temporary_class', (), {})