diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..7b272ac
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+### Python ###
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+.vscode/settings.json
diff --git a/diceplayer/player.py b/diceplayer/player.py
index 4229e08..2312d90 100644
--- a/diceplayer/player.py
+++ b/diceplayer/player.py
@@ -1,14 +1,15 @@
-from diceplayer.shared.config.step_dto import StepDTO
-from diceplayer.shared.environment.atom import Atom
+from diceplayer.shared.interface.gaussian_interface import GaussianInterface
+from diceplayer.shared.interface.dice_interface import DiceInterface
 from diceplayer.shared.utils.dataclass_protocol import Dataclass
 from diceplayer.shared.config.gaussian_dto import GaussianDTO
 from diceplayer.shared.environment.molecule import Molecule
-from diceplayer.shared.environment.system import System
 from diceplayer.shared.utils.misc import weekday_date_time
 from diceplayer.shared.config.player_dto import PlayerDTO
-from diceplayer.shared.interface.gaussian_interface import GaussianInterface
+from diceplayer.shared.environment.system import System
+from diceplayer.shared.config.step_dto import StepDTO
 from diceplayer.shared.config.dice_dto import DiceDTO
-from diceplayer.shared.interface.dice_interface import DiceInterface
+from diceplayer.shared.environment.atom import Atom
+from diceplayer.shared.utils.ptable import atommass
 
 from dataclasses import fields
 from pathlib import Path
@@ -18,7 +19,6 @@ import yaml
 import sys
 import os
 
-from diceplayer.shared.utils.ptable import atommass
 
 ENV = ["OMP_STACKSIZE"]
 
diff --git a/tests/shared/interface/test_dice_interface.py b/tests/shared/interface/test_dice_interface.py
index 1f54445..4698751 100644
--- a/tests/shared/interface/test_dice_interface.py
+++ b/tests/shared/interface/test_dice_interface.py
@@ -34,11 +34,11 @@ class TestDiceInterface(unittest.TestCase):
             }
         )
 
-        self.assertFalse(hasattr(dice, 'step'))
+        self.assertIsNone(dice.step)
 
         dice.configure('test')
 
-        self.assertTrue(hasattr(dice, 'step'))
+        self.assertIsNotNone(dice.step)
 
     def test_reset(self):
         dice = DiceInterface(