code: def get_inheritors(cls):
      
      subclasses = set()
      work = [cls]
      while work:
          parent = work.pop()
          for child in parent.__subclasses__():
              if child not in subclasses:
                  subclasses.add(child)
                  work.append(child)
      return subclasses
docs: Get a set of all classes that inherit from the given class.