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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 _parse_raid_config_data(self, raid_config):
 """It will parse raid config data based on raid controllers :param raid_config: A dictionary containing target raid configuration data. This data stucture should be as follows: raid_config = {'logical_disks': [{'raid_level': 1, 'size_gb': 100, 'controller': 'HPE Smart Array P408i-a SR Gen10'}, <info-for-logical-disk-2>]} :returns: A dictionary of controllers, each containing list of their respected logical drives. """

        default = (
            self.smart_storage.array_controllers.get_default_controller.model)
        controllers = {default: []}
        for ld in raid_config['logical_disks']:
            if 'controller' not in ld.keys():
                controllers[default].append(ld)
            else:
                ctrl = ld['controller']
                if ctrl not in controllers:
                    controllers[ctrl] = []
                controllers[ctrl].append(ld)
        return controllers