diff --git a/python/tvm/contrib/cudnn.py b/python/tvm/contrib/cudnn.py
index 918939589e44d..47d77999007d3 100644
--- a/python/tvm/contrib/cudnn.py
+++ b/python/tvm/contrib/cudnn.py
@@ -603,7 +603,9 @@ def conv_backward_data(x, w, pad, stride, dilation, conv_mode, tensor_format, co
 
     x_shape = list(x.shape)
 
-    assert isinstance(x.shape[0], tvm.tir.expr.IntImm), "Dynamic batch is not supported for cudnn conv2d backwad data yet."
+    assert isinstance(
+        x.shape[0], tvm.tir.expr.IntImm
+    ), "Dynamic batch is not supported for cudnn conv2d backwad data yet."
     # TODO: fix oshape
     oshape = x_shape
     if tensor_format == 0: