diff --git a/dpdata/abacus/scf.py b/dpdata/abacus/scf.py
index 1102f299d..87b95c287 100644
--- a/dpdata/abacus/scf.py
+++ b/dpdata/abacus/scf.py
@@ -688,7 +688,7 @@ def process_file_input(file_input, atom_names, input_name):
 
     if mag is None and data.get("spins") is not None and len(data["spins"]) > 0:
         mag = data["spins"][frame_idx]
-    
+
     if move is None and data.get("move", None) is not None and len(data["move"]) > 0:
         move = data["move"]
 
diff --git a/dpdata/vasp/poscar.py b/dpdata/vasp/poscar.py
index 7ece25357..5b73b71b1 100644
--- a/dpdata/vasp/poscar.py
+++ b/dpdata/vasp/poscar.py
@@ -113,10 +113,7 @@ def from_system_data(system, f_idx=0, skip_zeros=True):
         line = f"{ii_posi[0]:15.10f} {ii_posi[1]:15.10f} {ii_posi[2]:15.10f}"
         if len(move) > 0:
             move_flags = move[idx]
-            if (
-                isinstance(move_flags, list)
-                and len(move_flags) == 3
-            ):
+            if isinstance(move_flags, list) and len(move_flags) == 3:
                 line += " " + " ".join(["T" if flag else "F" for flag in move_flags])
             elif isinstance(move_flags, (int, float, bool)):
                 line += " " + " ".join(["T" if move_flags else "F"] * 3)
diff --git a/tests/test_vasp_poscar_dump.py b/tests/test_vasp_poscar_dump.py
index c04023fd1..d55228117 100644
--- a/tests/test_vasp_poscar_dump.py
+++ b/tests/test_vasp_poscar_dump.py
@@ -40,10 +40,10 @@ def test_dump_move_flags(self):
         tmp_system.to_vasp_poscar("tmp.POSCAR")
         self.system = dpdata.System()
         self.system.from_vasp_poscar("tmp.POSCAR")
-        with open("tmp.POSCAR", "r") as f:
+        with open("tmp.POSCAR") as f:
             content = f.read()
 
-        stru_ref = f"""Cartesian
+        stru_ref = """Cartesian
    0.0000000000    0.0000000000    0.0000000000 T T F
    1.2621856044    0.7018027835    0.5513883414 F F F
 """
diff --git a/tests/test_vasp_poscar_to_system.py b/tests/test_vasp_poscar_to_system.py
index 3e43afdf0..745c0bb7f 100644
--- a/tests/test_vasp_poscar_to_system.py
+++ b/tests/test_vasp_poscar_to_system.py
@@ -13,7 +13,7 @@ class TestPOSCARCart(unittest.TestCase, TestPOSCARoh):
     def setUp(self):
         self.system = dpdata.System()
         self.system.from_vasp_poscar(os.path.join("poscars", "POSCAR.oh.c"))
-    
+
     def test_move_flags(self):
         expected = np.array([[True, True, False], [False, False, False]])
         self.assertTrue(np.array_equal(self.system["move"], expected))