Merge branch 'dev' into release_1_5_1

Author: KumoLiu

monai/networks/nets/diffusion_model_unet.py

@@ -34,7 +34,6 @@
 import math
 from collections.abc import Sequence
 from functools import reduce
-from typing import Optional
 
 import numpy as np
 import torch
@@ -2016,7 +2015,7 @@ def __init__(
 
         last_dim_flattened = int(reduce(lambda x, y: x * y, input_shape) * channels[-1])
 
-        self.out: Optional[nn.Module] = nn.Sequential(
+        self.out: nn.Module = nn.Sequential(
             nn.Linear(last_dim_flattened, 512), nn.ReLU(), nn.Dropout(0.1), nn.Linear(512, self.out_channels)
         )
 
@@ -2063,9 +2062,6 @@ def forward(
         h = h.reshape(h.shape[0], -1)
 
         # 5. out
-        self.out = nn.Sequential(
-            nn.Linear(h.shape[1], 512), nn.ReLU(), nn.Dropout(0.1), nn.Linear(512, self.out_channels)
-        )
         output: torch.Tensor = self.out(h)
 
         return output