old_contents: from django.contrib.admin.options import FORMFIELD_FOR_DBFIELD_DEFAULTS
  from django.contrib.gis import admin
  from transport.models import Bus, Direction, Route, StopPoint, TimeSheet, Travel
  
  
  class StopPointInline(admin.OSMGeoAdmin, admin.StackedInline):
      model = StopPoint
  
      def __init__(self, parent_model, admin_site):
          self.admin_site = admin_site
          self.parent_model = parent_model
          self.opts = self.model._meta
          self.has_registered_model = admin_site.is_registered(self.model)
          overrides = FORMFIELD_FOR_DBFIELD_DEFAULTS.copy()
          overrides.update(self.formfield_overrides)
          self.formfield_overrides = overrides
          if self.verbose_name is None:
              self.verbose_name = self.model._meta.verbose_name
          if self.verbose_name_plural is None:
              self.verbose_name_plural = self.model._meta.verbose_name_plural
  
  
  class RouteAdmin(admin.ModelAdmin):
      inlines = (StopPointInline,)
  
  
  class TravelInline(admin.TabularInline):
      model = Travel
  
  
  class TimeSheetAdmin(admin.ModelAdmin):
      inlines = (TravelInline,)
  
  
  admin.site.register(Bus)
  admin.site.register(Direction)
  admin.site.register(Route, RouteAdmin)
  admin.site.register(TimeSheet, TimeSheetAdmin)
  
new_contents: from django.contrib.admin.options import FORMFIELD_FOR_DBFIELD_DEFAULTS
  from django.contrib.gis import admin
  from transport.models import Bus, Direction, Route, StopPoint, TimeSheet, Travel
  
  
  class StopPointInline(admin.OSMGeoAdmin, admin.StackedInline):
      model = StopPoint
  
      def __init__(self, parent_model, admin_site):
          self.admin_site = admin_site
          self.parent_model = parent_model
          self.opts = self.model._meta
          self.has_registered_model = admin_site.is_registered(self.model)
          overrides = FORMFIELD_FOR_DBFIELD_DEFAULTS.copy()
          overrides.update(self.formfield_overrides)
          self.formfield_overrides = overrides
          if self.verbose_name is None:
              self.verbose_name = self.model._meta.verbose_name
          if self.verbose_name_plural is None:
              self.verbose_name_plural = self.model._meta.verbose_name_plural
  
  
  class RouteAdmin(admin.ModelAdmin):
      inlines = (StopPointInline,)
      list_display = ('name', 'organization')
  
  
  class TravelInline(admin.TabularInline):
      model = Travel
  
  
  class TimeSheetAdmin(admin.ModelAdmin):
      inlines = (TravelInline,)
      list_display = ('direction', 'version', 'validity', 'organization')
  
  
  class BusAdmin(admin.ModelAdmin):
      list_display = ('name', 'organization')
  
  
  class DirectionAdmin(admin.ModelAdmin):
      list_display = ('name', 'organization')
  
  
  admin.site.register(Bus, BusAdmin)
  admin.site.register(Direction, DirectionAdmin)
  admin.site.register(Route, RouteAdmin)
  admin.site.register(TimeSheet, TimeSheetAdmin)
  
subject: Add list_display to the model admins