def get_freeze_filter(self) -> nnx.filterlib.Filter:
        """Returns the freeze filter based on the model config."""
        if "lora" in self.paligemma_variant:
            return nnx.All(nnx_utils.PathRegex(".*llm.*"), nnx.Not(nnx_utils.PathRegex(".*lora.*")))
        return nnx.Nothing
Returns the freeze filter based on the model config.
policy/openpi/src/openpi/models/pi0_fast.py