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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 save_config(self, config_file_name):
 """ Save configuration file from prt or str. Configuration file type is extracted from the file suffix - prt or str. :param config_file_name: full path to the configuration file. IxTclServer must have access to the file location. either: The config file is on shared folder. IxTclServer run on the client machine. """

        config_file_name = config_file_name.replace('\\', '/')
        ext = path.splitext(config_file_name)[-1].lower()
        if ext == '.prt':
            self.api.call_rc('port export "{}" {}'.format(config_file_name, self.uri))
        elif ext == '.str':
            # self.reset()
            self.api.call_rc('stream export "{}" {}'.format(config_file_name, self.uri))
        else:
            raise ValueError('Configuration file type {} not supported.'.format(ext))