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# -*- coding: utf-8 -*-
"""
Null object
~~~~~~~~~~~~~~~~~~~~~~~~~~~~
Simple implementation of the Null Object Pattern.
Taken from "Implementing the Null Object Pattern" recipe from
the Python CookBook.
:url: https://www.safaribooksonline.com/library/view/python-cookbook/0596001673/ch05s24.html
:credit: Dinu C. Gherman
:copyright: Copyright (c) 2012-2015 Scott Bahling, SUSE Linux GmbH
:license: GPL-2.0, see COPYING for details
"""
class Null:
""" Null objects always and reliably "do nothing." """
def __init__(self, *args, **kwargs):
pass
def __call__(self, *args, **kwargs):
return self
def __repr__(self):
return "Null( )"
def __str__(self):
return ""
def __nonzero__(self):
return 0
def __getattr__(self, name):
return self
def __setattr__(self, name, value):
return self
def __delattr__(self, name):
return self
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