diff --git a/source/lmp/fix_dplr.cpp b/source/lmp/fix_dplr.cpp
index 2149b11b0a..3e59c6b2db 100644
--- a/source/lmp/fix_dplr.cpp
+++ b/source/lmp/fix_dplr.cpp
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: LGPL-3.0-or-later
 #include "fix_dplr.h"
 
 #include <iomanip>
diff --git a/source/lmp/tests/test_dplr.py b/source/lmp/tests/test_dplr.py
index 24f39d755b..8da142436b 100644
--- a/source/lmp/tests/test_dplr.py
+++ b/source/lmp/tests/test_dplr.py
@@ -387,7 +387,9 @@ def test_pair_deepmd_lr(lammps):
     lammps.special_bonds("lj/coul 1 1 1 angle no")
     lammps.kspace_style("pppm/dplr 1e-5")
     lammps.kspace_modify(f"gewald {beta:.2f} diff ik mesh {mesh:d} {mesh:d} {mesh:d}")
-    lammps.fix(f"0 all dplr model {pb_file.resolve()} type_associate 1 3 bond_type 1 pair_deepmd_index 0")
+    lammps.fix(
+        f"0 all dplr model {pb_file.resolve()} type_associate 1 3 bond_type 1 pair_deepmd_index 0"
+    )
     lammps.fix_modify("0 virial yes")
     lammps.run(0)
     for ii in range(8):
@@ -484,7 +486,9 @@ def test_min_dplr(lammps):
     lammps.special_bonds("lj/coul 1 1 1 angle no")
     lammps.kspace_style("pppm/dplr 1e-5")
     lammps.kspace_modify(f"gewald {beta:.2f} diff ik mesh {mesh:d} {mesh:d} {mesh:d}")
-    lammps.fix(f"0 all dplr model {pb_file.resolve()} type_associate 1 3 bond_type 1 pair_deepmd_index 0")
+    lammps.fix(
+        f"0 all dplr model {pb_file.resolve()} type_associate 1 3 bond_type 1 pair_deepmd_index 0"
+    )
     lammps.fix_modify("0 virial yes")
     lammps.min_style("cg")
     lammps.minimize("0 1.0e-6 2 2")