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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 load_configuration_file(self, configuration_file):
 """ Load configuration defaults from a configuration file. :param configuration_file: The pathname of a configuration file (a string). :raises: :exc:`Exception` when the configuration file cannot be loaded. """

        configuration_file = parse_path(configuration_file)
        logger.debug("Loading configuration file: %s", configuration_file)
        parser = configparser.RawConfigParser()
        files_loaded = parser.read(configuration_file)
        if len(files_loaded) != 1:
            msg = "Failed to load configuration file! (%s)"
            raise Exception(msg % configuration_file)
        elif not parser.has_section('pip-accel'):
            msg = "Missing 'pip-accel' section in configuration file! (%s)"
            raise Exception(msg % configuration_file)
        else:
            self.configuration.update(parser.items('pip-accel'))