Track bundled vendor runtime sources

vendor/ComfyUI/comfy_extras/nodes_pag.py

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+#Modified/simplified version of the node from: https://github.com/pamparamm/sd-perturbed-attention
+#If you want the one with more options see the above repo.
+
+#My modified one here is more basic but has less chances of breaking with ComfyUI updates.
+
+from typing_extensions import override
+
+import comfy.model_patcher
+import comfy.samplers
+from comfy_api.latest import ComfyExtension, io
+
+
+class PerturbedAttentionGuidance(io.ComfyNode):
+    @classmethod
+    def define_schema(cls):
+        return io.Schema(
+            node_id="PerturbedAttentionGuidance",
+            category="model/patch/unet",
+            inputs=[
+                io.Model.Input("model"),
+                io.Float.Input("scale", default=3.0, min=0.0, max=100.0, step=0.01, round=0.01),
+            ],
+            outputs=[
+                io.Model.Output(),
+            ],
+        )
+
+    @classmethod
+    def execute(cls, model, scale) -> io.NodeOutput:
+        unet_block = "middle"
+        unet_block_id = 0
+        m = model.clone()
+
+        def perturbed_attention(q, k, v, extra_options, mask=None):
+            return v
+
+        def post_cfg_function(args):
+            model = args["model"]
+            cond_pred = args["cond_denoised"]
+            cond = args["cond"]
+            cfg_result = args["denoised"]
+            sigma = args["sigma"]
+            model_options = args["model_options"].copy()
+            x = args["input"]
+
+            if scale == 0:
+                return cfg_result
+
+            # Replace Self-attention with PAG
+            model_options = comfy.model_patcher.set_model_options_patch_replace(model_options, perturbed_attention, "attn1", unet_block, unet_block_id)
+            (pag,) = comfy.samplers.calc_cond_batch(model, [cond], x, sigma, model_options)
+
+            return cfg_result + (cond_pred - pag) * scale
+
+        m.set_model_sampler_post_cfg_function(post_cfg_function)
+
+        return io.NodeOutput(m)
+
+
+class PAGExtension(ComfyExtension):
+    @override
+    async def get_node_list(self) -> list[type[io.ComfyNode]]:
+        return [
+            PerturbedAttentionGuidance,
+        ]
+
+
+async def comfy_entrypoint() -> PAGExtension:
+    return PAGExtension()