Remove unnecessary use of FusedLayerNorm

pytorch_transformers/modeling_bert.py

@@ -133,11 +133,7 @@ def swish(x):
 ACT2FN = {"gelu": gelu, "relu": torch.nn.functional.relu, "swish": swish}
 
 
-try:
-    from apex.normalization.fused_layer_norm import FusedLayerNorm as BertLayerNorm
-except (ImportError, AttributeError) as e:
-    logger.info("Better speed can be achieved with apex installed from https://www.github.com/nvidia/apex .")
-    BertLayerNorm = torch.nn.LayerNorm
+BertLayerNorm = torch.nn.LayerNorm
 
 class BertEmbeddings(nn.Module):
     """Construct the embeddings from word, position and token_type embeddings.