docs: def get_classes_in_module(module, superclass=object):
      """
      Returns a list with all classes in module that descend from parent
  
      Args:
          module: builtins.module
          superclass: a class
  
      Returns: list
      """
  
      ret = []
      for classname in dir(module):
          attr = module.__getattribute__(classname)
          try:
              if issubclass(attr, superclass) and (attr != superclass):
                  ret.append(attr)
          except TypeError:
              # "issubclass() arg 1 must be a class"
              pass
          except RuntimeError:
              # a99.get_python_logger().exception("Failed probing attribute '{}'".format(classname))
              # raise
              pass
      return ret