Fix bug where is_using_v_parameterization_for_sd2 fails because the sd_hijack...

Fix bug where is_using_v_parameterization_for_sd2 fails because the sd_hijack is only partially undone

modules/sd_hijack.py

@@ -38,9 +38,6 @@ ldm.models.diffusion.ddpm.print = shared.ldm_print
 optimizers = []
 current_optimizer: sd_hijack_optimizations.SdOptimization = None
 
-ldm_original_forward = patches.patch(__file__, ldm.modules.diffusionmodules.openaimodel.UNetModel, "forward", sd_unet.UNetModel_forward)
-sgm_original_forward = patches.patch(__file__, sgm.modules.diffusionmodules.openaimodel.UNetModel, "forward", sd_unet.UNetModel_forward)
-
 def list_optimizers():
     new_optimizers = script_callbacks.list_optimizers_callback()
 
@@ -258,6 +255,9 @@ class StableDiffusionModelHijack:
 
         import modules.models.diffusion.ddpm_edit
 
+        ldm_original_forward = patches.patch(__file__, ldm.modules.diffusionmodules.openaimodel.UNetModel, "forward", sd_unet.UNetModel_forward)
+        sgm_original_forward = patches.patch(__file__, sgm.modules.diffusionmodules.openaimodel.UNetModel, "forward", sd_unet.UNetModel_forward)
+
         if isinstance(m, ldm.models.diffusion.ddpm.LatentDiffusion):
             sd_unet.original_forward = ldm_original_forward
         elif isinstance(m, modules.models.diffusion.ddpm_edit.LatentDiffusion):
@@ -303,6 +303,9 @@ class StableDiffusionModelHijack:
         self.layers = None
         self.clip = None
 
+        patches.undo(__file__, ldm.modules.diffusionmodules.openaimodel.UNetModel, "forward")
+        patches.undo(__file__, sgm.modules.diffusionmodules.openaimodel.UNetModel, "forward")
+
         sd_unet.original_forward = None