old_contents: from markitup.fields import MarkupField
  import widgets
  
  class MarkupFilebrowserFiled(MarkupField):
      def formfield(self, **kwargs):
          defaults = {'widget': widgets.MarkitUpFilebrowserWiget}
          defaults.update(kwargs)
          return super(MarkupFilebrowserFiled, self).formfield(**defaults)
  
  
  from django.contrib.admin.options import FORMFIELD_FOR_DBFIELD_DEFAULTS
  FORMFIELD_FOR_DBFIELD_DEFAULTS[MarkupFilebrowserFiled] = {'widget': widgets.AdminMarkitUpFilebrowserWiget}
new_contents: from markitup.fields import MarkupField
  import widgets
  
  class MarkupFilebrowserFiled(MarkupField):
      def formfield(self, **kwargs):
          defaults = {'widget': widgets.MarkitUpFilebrowserWiget}
          defaults.update(kwargs)
          return super(MarkupFilebrowserFiled, self).formfield(**defaults)
  
  
  from django.contrib.admin.options import FORMFIELD_FOR_DBFIELD_DEFAULTS
  FORMFIELD_FOR_DBFIELD_DEFAULTS[MarkupFilebrowserFiled] = {'widget': widgets.AdminMarkitUpFilebrowserWiget}
  
  
  # allow South to handle MarkupField smoothly
  try:
      from south.modelsinspector import add_introspection_rules
      # For a normal MarkupField, the add_rendered_field attribute is
      # always True, which means no_rendered_field arg will always be
      # True in a frozen MarkupField, which is what we want.
      add_introspection_rules(rules=[((MarkupFilebrowserFiled,),
                                      [],
                                      {'no_rendered_field': ('add_rendered_field',
                                                             {})})],
          patterns=['markitup_filebrowser\.fields\.'])
  except ImportError:
      pass
  
subject: Allow south to handle MarkupFilebrowserFiled