code: def test_enum(self):
      # the Interpretation enum is created when the first image is made --
      # make it ourselves in case we are run before the first image
      pyvips.vips_lib.vips_interpretation_get_type()
      interpretation_gtype = pyvips.gobject_lib.g_type_from_name(
          b"VipsInterpretation"
      )
      gv = pyvips.GValue()
      gv.set_type(interpretation_gtype)
      gv.set("xyz")
      value = gv.get()
      assert value == "xyz"
  
file_path: pyvips/tests/test_gvalue.py
imports: import pytest
  import pyvips
  from helpers import JPEG_FILE, assert_almost_equal_objects
label_desc: Use image node_id 5 for calling the TestGValue obj's underlying member method code with example usage: obj.test_enum() without return types