diff --git a/docs/conf.py b/docs/conf.py
index a40422d3..263cb550 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -24,7 +24,7 @@
 # -- Project information -----------------------------------------------------
 
 project = "dpdata"
-copyright = "2019-%d, DeepModeling " % date.today().year
+copyright = "2019-%d, DeepModeling " % date.today().year  # noqa: UP031
 author = "Han Wang"
 
 # The short X.Y version
diff --git a/tests/poscars/poscar_ref_oh.py b/tests/poscars/poscar_ref_oh.py
index 2d29aeeb..39299ff8 100644
--- a/tests/poscars/poscar_ref_oh.py
+++ b/tests/poscars/poscar_ref_oh.py
@@ -32,7 +32,7 @@ def test_cell(self):
                     self.system.data["cells"][0][ii][jj],
                     ovito_cell[ii][jj],
                     places=6,
-                    msg="cell[%d][%d] failed" % (ii, jj),
+                    msg="cell[%d][%d] failed" % (ii, jj),  # noqa: UP031
                 )
 
     def test_frame(self):
@@ -48,5 +48,5 @@ def test_frame(self):
                     self.system.data["coords"][0][ii][jj],
                     ovito_posis[ii][jj],
                     places=6,
-                    msg="posis[%d][%d] failed" % (ii, jj),
+                    msg="posis[%d][%d] failed" % (ii, jj),  # noqa: UP031
                 )
diff --git a/tests/pwmat/config_ref_ch4.py b/tests/pwmat/config_ref_ch4.py
index 72499398..bb76f6cf 100644
--- a/tests/pwmat/config_ref_ch4.py
+++ b/tests/pwmat/config_ref_ch4.py
@@ -35,7 +35,7 @@ def test_cell(self):
                     self.system.data["cells"][0][ii][jj],
                     ovito_cell[ii][jj],
                     places=6,
-                    msg="cell[%d][%d] failed" % (ii, jj),
+                    msg="cell[%d][%d] failed" % (ii, jj),  # noqa: UP031
                 )
 
     def test_frame(self):
@@ -57,5 +57,5 @@ def test_frame(self):
                     self.system.data["coords"][0][ii][jj],
                     ovito_posis[ii][jj],
                     places=6,
-                    msg="posis[%d][%d] failed" % (ii, jj),
+                    msg="posis[%d][%d] failed" % (ii, jj),  # noqa: UP031
                 )
diff --git a/tests/pwmat/config_ref_oh.py b/tests/pwmat/config_ref_oh.py
index ad546019..cde0e3ec 100644
--- a/tests/pwmat/config_ref_oh.py
+++ b/tests/pwmat/config_ref_oh.py
@@ -32,7 +32,7 @@ def test_cell(self):
                     self.system.data["cells"][0][ii][jj],
                     ovito_cell[ii][jj],
                     places=6,
-                    msg="cell[%d][%d] failed" % (ii, jj),
+                    msg="cell[%d][%d] failed" % (ii, jj),  # noqa: UP031
                 )
 
     def test_frame(self):
@@ -43,5 +43,5 @@ def test_frame(self):
                     self.system.data["coords"][0][ii][jj],
                     ovito_posis[ii][jj],
                     places=6,
-                    msg="posis[%d][%d] failed" % (ii, jj),
+                    msg="posis[%d][%d] failed" % (ii, jj),  # noqa: UP031
                 )
diff --git a/tests/test_custom_data_type.py b/tests/test_custom_data_type.py
index 230475ab..08dc9eba 100644
--- a/tests/test_custom_data_type.py
+++ b/tests/test_custom_data_type.py
@@ -120,4 +120,6 @@ def test_to_deepmd_hdf5(self):
     def test_from_deepmd_hdf5(self):
         self.system.to_deepmd_hdf5("data_bar.h5")
         x = dpdata.LabeledSystem("data_bar.h5", fmt="deepmd/hdf5")
+        print(self.system.data.keys())
+        print(x.data.keys())
         np.testing.assert_allclose(x.data["bar"], self.bar)
diff --git a/tests/test_msd.py b/tests/test_msd.py
index 7148b0b5..5d26db64 100644
--- a/tests/test_msd.py
+++ b/tests/test_msd.py
@@ -28,6 +28,6 @@ def test_msd(self):
         # print(msd)
         ncomp = msd.shape[0]
         for ii in range(ncomp):
-            self.assertAlmostEqual(msd0[ii], ii * ii, msg="msd0[%d]" % ii)
-            self.assertAlmostEqual(msd1[ii], ii * ii * 4, msg="msd1[%d]" % ii)
-            self.assertAlmostEqual(msd[ii], (msd0[ii] + msd1[ii]) * 0.5, "msd[%d]" % ii)
+            self.assertAlmostEqual(msd0[ii], ii * ii, msg="msd0[%d]" % ii)  # noqa: UP031
+            self.assertAlmostEqual(msd1[ii], ii * ii * 4, msg="msd1[%d]" % ii)  # noqa: UP031
+            self.assertAlmostEqual(msd[ii], (msd0[ii] + msd1[ii]) * 0.5, "msd[%d]" % ii)  # noqa: UP031
diff --git a/tests/test_remove_pbc.py b/tests/test_remove_pbc.py
index d70a2f02..7770b6fd 100644
--- a/tests/test_remove_pbc.py
+++ b/tests/test_remove_pbc.py
@@ -39,7 +39,7 @@ def test_remove(self):
                     self.assertAlmostEqual(
                         sys["cells"][ff][ii][jj],
                         ref[ii][jj],
-                        msg="%d %d %d" % (ff, ii, jj),
+                        msg="%d %d %d" % (ff, ii, jj),  # noqa: UP031
                     )
             dists = []
             for ii in range(sys.get_natoms()):
diff --git a/tests/test_system_apply_pbc.py b/tests/test_system_apply_pbc.py
index 2114cf6a..22dab3ba 100644
--- a/tests/test_system_apply_pbc.py
+++ b/tests/test_system_apply_pbc.py
@@ -27,7 +27,7 @@ def test_pbc(self):
                     self.assertAlmostEqual(
                         sys["coords"][ii][jj][dd],
                         bk_coord[ii][jj][dd],
-                        msg="coord[%d][%d][%d] failed" % (ii, jj, dd),
+                        msg="coord[%d][%d][%d] failed" % (ii, jj, dd),  # noqa: UP031
                     )