code: def cls_slots(self, cls: CLASS_OR_CLASSNAME) -> List[SlotDefinition]:
          
          if not isinstance(cls, ClassDefinition):
              cls = self.schema.classes[cls]
          return [self.schema.slots[s] for s in cls.slots]
docs: Return the list of slots directly included in the class definition.  Includes slots whose
          domain is cls -- as declared in slot.domain or class.slots
  
          Does not include slots declared in mixins, apply_to or is_a links
  
          @param cls: class name or class definition name
          @return: all direct class slots