code: def ip_prefixes_sanity_check(config, bird_configuration):
      
      for ip_version in bird_configuration:
          modify_ip_prefixes(config,
                             bird_configuration[ip_version]['config_file'],
                             bird_configuration[ip_version]['variable_name'],
                             bird_configuration[ip_version]['dummy_ip_prefix'],
                             bird_configuration[ip_version]['reconfigure_cmd'],
                             bird_configuration[ip_version]['keep_changes'],
                             bird_configuration[ip_version]['changes_counter'],
                             ip_version)
docs: Sanity check on IP prefixes.
  
      Arguments:
          config (obg): A configparser object which holds our configuration.
          bird_configuration (dict): A dictionary, which holds Bird configuration
          per IP protocol version.