diff --git a/tutorial-contents/501_why_torch_dynamic_graph.py b/tutorial-contents/501_why_torch_dynamic_graph.py
index e1c4133..90b4f3e 100644
--- a/tutorial-contents/501_why_torch_dynamic_graph.py
+++ b/tutorial-contents/501_why_torch_dynamic_graph.py
@@ -16,11 +16,8 @@ import matplotlib.pyplot as plt
 torch.manual_seed(1)    # reproducible
 
 # Hyper Parameters
-BATCH_SIZE = 64
-TIME_STEP = 5           # rnn time step / image height
 INPUT_SIZE = 1          # rnn input size / image width
 LR = 0.02               # learning rate
-DOWNLOAD_MNIST = True   # set to False if have downloaded the data
 
 
 class RNN(nn.Module):