To have an importance value for each feature, a wikipedia helper table is downloaded from a Nominatim server. This is the same information Nominatim uses to determine the importance. It was decided to take this pre-calculated data instead of calculating it due to longer processing times (up to several days!). Also, the same calculations are applied, to achieve the same results. The initialization of the database is skipped, if it is already present.
The download and import of the wikipedia dump are skipped, if it is already present. Since the dump was created with the username brian, a temporary user is created to restore the dump, which is dropped after transferring the ownership to the osm user.