def test_source_putaround_simple():

       source = Source("raise ValueError")

       source = source.putaround(

           "try:", """\

           except ValueError:

               x = 42

           else:

->             x = 23""")

       assert str(source)=="""\

   try:

       raise ValueError

   except ValueError:

       x = 42

   else:

       x = 23"""