code: def rc_notfound(cls, interface_type, resource_name=None):
          
  
          msg = "Resource class for %s not provided and default not found." % interface_type
  
          if resource_name:
              msg = "Could not parse '%s'. %s" % (resource_name, msg)
  
          return cls(msg)
docs: Exception used when no resource class is provided and no default is found.