text: import inspect
  
  
  def list_classes_from_module(module, parent_class=None):
      """
      Parse user defined module to get all model service classes in it.
  
      :param module:
      :param parent_class:
      :return: List of model service class definitions
      """
  
      # Parsing the module to get all defined classes
      classes = [cls[1] for cls in inspect.getmembers(module, lambda member: inspect.isclass(member) and
                                                      member.__module__ == module.__name__)]
      # filter classes that is subclass of parent_class
      if parent_class is not None:
          return [c for c in classes if issubclass(c, parent_class)]
  
      return classes
  