Uses GTFS data to create unique trip variants.

Creates complete geometri and joins attributes.

Trip variants means of a transport line have multiple destinations, one feature is created per trip variation and direction. So ex bus line 1 can have Start_Headsign A but different stop_headsignes, and will therefor be 2 attributes with different geometries.

route_main_mode is added according to GTFS standard Extended GTFS Route Types | Static Transit | Google for Developers

See help if you want just one line per route, ex bus 1 as one line.