Use Python 3.9 syntax in examples (#37279)

Signed-off-by: cyy <cyyever@outlook.com>

examples/modular-transformers/modeling_add_function.py

@@ -5,7 +5,7 @@
 #                          modular_add_function.py file directly. One of our CI enforces this.
 #                🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨🚨
 # Note that zamba does not have the `apply_rotary_pos_emb` function!
-from typing import Optional, Tuple
+from typing import Optional
 
 import torch
 from torch import nn
@@ -62,5 +62,5 @@ class TestAttention(nn.Module):
     def __init__(self):
         pass
 
-    def forward(self) -> Tuple[torch.Tensor, Optional[torch.Tensor], Optional[Tuple[torch.Tensor]]]:
+    def forward(self) -> tuple[torch.Tensor, Optional[torch.Tensor], Optional[tuple[torch.Tensor]]]:
         _ = apply_rotary_pos_emb(1, 1, 1, 1)