fix import (#30)

- fix import (150762d848965ff65da1754465462b83a6d1c1e2)


Co-authored-by: Vitaliy Chiley <vchiley@users.noreply.huggingface.co>

attention.py

@@ -5,6 +5,7 @@ from typing import Optional
 import torch
 import torch.nn as nn
 from einops import rearrange
+from packaging import version
 from torch import nn
 from .norm import LPLayerNorm