text: from sqlalchemy.orm import relationship
  
  from libweasyl.models.meta import Base
  from libweasyl.models.users import Login
  from libweasyl.models import tables
  
  
  class SiteUpdate(Base):
      __table__ = tables.siteupdate
  
      owner = relationship(Login, backref='siteupdate')
  
      def canonical_path(self, request, operation='view'):
          parts = ['site-updates', str(self.updateid)]
  
          if operation in ('delete', 'edit'):
              parts.append(operation)
  
          return request.resource_path(None, *parts)
  
  
  class SavedNotification(Base):
      __table__ = tables.welcome
  
      owner = relationship(Login, backref='saved_notifications')
  