missing commas and backwards return arguments (#1032)

* missing commas

* another fix

flash_attn/flash_attn_interface.py

@@ -286,7 +286,7 @@ class FlashAttnQKVPackedFunc(torch.autograd.Function):
             rng_state=rng_state,
         )
         dqkv = dqkv[..., : dout.shape[-1]]  # We could have padded the head dimension
-        return dqkv, None, None, None, None, None, None, None
+        return dqkv, None, None, None, None, None, None, None, None
 
 
 class FlashAttnVarlenQKVPackedFunc(torch.autograd.Function):
@@ -511,7 +511,7 @@ class FlashAttnVarlenKVPackedFunc(torch.autograd.Function):
         )
         dq = dq[..., : dout.shape[-1]]  # We could have padded the head dimension
         dkv = dkv[..., : dout.shape[-1]]
-        return dq, dkv, None, None, None, None, None, None, None, None, None, None, None
+        return dq, dkv, None, None, None, None, None, None, None, None, None, None, None, None
 
 
 class FlashAttnFunc(torch.autograd.Function):
@@ -572,7 +572,7 @@ class FlashAttnFunc(torch.autograd.Function):
             ctx.softmax_scale,
             ctx.causal,
             ctx.window_size,
-            ctx.softcap
+            ctx.softcap,
             ctx.alibi_slopes,
             ctx.deterministic,
             rng_state=rng_state,
@@ -580,7 +580,7 @@ class FlashAttnFunc(torch.autograd.Function):
         dq = dq[..., : dout.shape[-1]]  # We could have padded the head dimension
         dk = dk[..., : dout.shape[-1]]
         dv = dv[..., : dout.shape[-1]]
-        return dq, dk, dv, None, None, None, None, None, None, None
+        return dq, dk, dv, None, None, None, None, None, None, None, None
 
 
 class FlashAttnVarlenFunc(torch.autograd.Function):
@@ -659,7 +659,7 @@ class FlashAttnVarlenFunc(torch.autograd.Function):
             ctx.softmax_scale,
             ctx.causal,
             ctx.window_size,
-            ctx.softcap
+            ctx.softcap,
             ctx.alibi_slopes,
             ctx.deterministic,
             rng_state=rng_state,
@@ -667,7 +667,7 @@ class FlashAttnVarlenFunc(torch.autograd.Function):
         dq = dq[..., : dout.shape[-1]]  # We could have padded the head dimension
         dk = dk[..., : dout.shape[-1]]
         dv = dv[..., : dout.shape[-1]]
-        return dq, dk, dv, None, None, None, None, None, None, None, None, None, None, None, None
+        return dq, dk, dv, None, None, None, None, None, None, None, None, None, None, None, None, None
 
 
 def flash_attn_qkvpacked_func(