diff --git a/BLcourse2.3/01_one_dim.py b/BLcourse2.3/01_one_dim.py
index b1e29e7d8297b3afc726ba786336ef57f99dc4a2..f9f8f95d68ab4407e5e58e6acf22cc21a337b483 100644
--- a/BLcourse2.3/01_one_dim.py
+++ b/BLcourse2.3/01_one_dim.py
@@ -311,7 +311,7 @@ for ii in range(n_iter):
     loss.backward()
     optimizer.step()
     if (ii + 1) % 10 == 0:
-        print(f"iter {ii+1}/{n_iter}, {loss=:.3f}")
+        print(f"iter {ii + 1}/{n_iter}, {loss=:.3f}")
     for p_name, p_val in extract_model_params(model).items():
         history[p_name].append(p_val)
     history["loss"].append(loss.item())
diff --git a/BLcourse2.3/02_two_dim.py b/BLcourse2.3/02_two_dim.py
index d13e54509eaf71971e2a5b75d642eabafda8c37f..348949586aba23911d52bbf6cbcb118608cca49c 100644
--- a/BLcourse2.3/02_two_dim.py
+++ b/BLcourse2.3/02_two_dim.py
@@ -236,7 +236,7 @@ for ii in range(n_iter):
     loss.backward()
     optimizer.step()
     if (ii + 1) % 10 == 0:
-        print(f"iter {ii+1}/{n_iter}, {loss=:.3f}")
+        print(f"iter {ii + 1}/{n_iter}, {loss=:.3f}")
     for p_name, p_val in extract_model_params(model).items():
         history[p_name].append(p_val)
     history["loss"].append(loss.item())