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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 process_app_config(config, config_data):
 """ Populates config with data from the configuration data dict. It handles everything that process_config does plus application section. :param config: The config reference of the object that will hold the configuration data from the config_data. :param config_data: The configuration data loaded from a configuration file. """

    process_config(config, config_data)

    # If apps is on config data, this is running o multi app mode
    if 'apps' in config_data:
        config.app['multi'] = True
        process_apps_config_session(config, config_data['apps'])
    else:
        # If not the app definition is on the firenado config file
        if 'app' in config_data:
            process_app_config_section(config, config_data['app'])