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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_config_file(self, config_data, indent=2):
 """write config data to file. Parameters ========== config_data: the Configuration object to save a username and password, if defined indent: number of tab indentations to use when writing json """

        with open(self.config, 'w') as f:
            json.dump(config_data, f, indent=indent)