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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 write_ioc_to_file(self, output_dir=None, force=False):
 """ Serialize the IOC to a .ioc file. :param output_dir: Directory to write the ioc out to. default is the current working directory. :param force: If specified, will not validate the root node of the IOC is 'OpenIOC'. :return: """

        return write_ioc(self.root, output_dir, force=force)