text: from dagster import PythonObjectDagsterType, make_python_type_usable_as_dagster_type, solid
  
  
  class EvenType:
      def __init__(self, num):
          assert num % 2 is 0
          self.num = num
  
  
  EvenDagsterType = PythonObjectDagsterType(EvenType, name="EvenDagsterType")
  
  make_python_type_usable_as_dagster_type(EvenType, EvenDagsterType)
  
  
  @solid
  def double_even(even_num: EvenType) -> EvenType:
      return EvenType(even_num.num * 2)
  