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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def append_config_item(self, key, value):
 """ Append 'value' to 'key', assuming 'key' is a list. If 'key' isn't a list, 'value' will be set as the value of 'key'. """


        return _lxc.Container.set_config_item(self, key, value)