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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_addon_packages(self, config_data):
 """ Loads the module paths from which the configuration will attempt to load sanitizers from. These must be stored as a list of strings under "config.addons" section of the configuration data. :param config_data: Already parsed configuration data, as dictionary. :type config_data: dict[str,any] """

        section_config = config_data.get("config")
        if not isinstance(section_config, dict):
            if section_config is None:
                return
            raise ConfigurationError(
                "'config' is %s instead of dict" % (
                    type(section_config),
                ),
            )

        section_addons = section_config.get("addons", [])
        if not isinstance(section_addons, list):
            raise ConfigurationError(
                "'config.addons' is %s instead of list" % (
                    type(section_addons),
                ),
            )

        for index, module_path in enumerate(section_addons):
            if not isinstance(module_path, six.text_type):
                raise ConfigurationError(
                    "Item %d in 'config.addons' is %s instead of string" % (
                        index,
                        type(module_path),
                    ),
                )

        self.addon_packages = list(section_addons)