diff --git a/src/mxdev/tests/conftest.py b/src/mxdev/tests/conftest.py
index 66c8ca9..a119b36 100644
--- a/src/mxdev/tests/conftest.py
+++ b/src/mxdev/tests/conftest.py
@@ -1,6 +1,7 @@
+from .utils import Process
+
 import os
 import pytest
-from .utils import Process
 
 
 @pytest.fixture
@@ -41,15 +42,18 @@ def git_allow_file_protocol():
     This is needed for the submodule to be added from a local path
     """
     from .utils import GitRepo
-    
+
     shell = Process()
-    file_allow = shell.check_call("git config --global --get protocol.file.allow")[0].decode("utf8").strip()
+    file_allow = (
+        shell.check_call("git config --global --get protocol.file.allow")[0]
+        .decode("utf8")
+        .strip()
+    )
     shell.check_call(f"git config --global protocol.file.allow always")
     yield file_allow
     shell.check_call(f"git config --global protocol.file.allow {file_allow}")
 
 
-
 @pytest.fixture
 def develop(src):
     from mxdev.tests.utils import MockDevelop
diff --git a/src/mxdev/tests/test_git_submodules.py b/src/mxdev/tests/test_git_submodules.py
index 24b6856..3c25cd1 100644
--- a/src/mxdev/tests/test_git_submodules.py
+++ b/src/mxdev/tests/test_git_submodules.py
@@ -102,7 +102,9 @@ def test_checkout_with_two_submodules(mkgitrepo, src, git_allow_file_protocol):
 @pytest.mark.skipif(
     condition=os.name == "nt", reason="submodules seem not to work on windows"
 )
-def test_checkout_with_two_submodules_recursive(mkgitrepo, src, git_allow_file_protocol):
+def test_checkout_with_two_submodules_recursive(
+    mkgitrepo, src, git_allow_file_protocol
+):
     """
     Tests the checkout of a module 'egg' with a submodule 'submodule_a'
     and a submodule 'submodule_b' in it.
@@ -297,7 +299,9 @@ def test_checkout_with_submodules_option_never(mkgitrepo, src, git_allow_file_pr
 @pytest.mark.skipif(
     condition=os.name == "nt", reason="submodules seem not to work on windows"
 )
-def test_checkout_with_submodules_option_never_source_always(mkgitrepo, src, git_allow_file_protocol):
+def test_checkout_with_submodules_option_never_source_always(
+    mkgitrepo, src, git_allow_file_protocol
+):
     """
     Tests the checkout of a module 'egg' with a submodule 'submodule_a' in it
     and a module 'egg2' with the same submodule, initializing only the submodule
@@ -358,7 +362,9 @@ def test_checkout_with_submodules_option_never_source_always(mkgitrepo, src, git
 @pytest.mark.skipif(
     condition=os.name == "nt", reason="submodules seem not to work on windows"
 )
-def test_checkout_with_submodules_option_always_source_never(mkgitrepo, src, git_allow_file_protocol):
+def test_checkout_with_submodules_option_always_source_never(
+    mkgitrepo, src, git_allow_file_protocol
+):
     """
     Tests the checkout of a module 'egg' with a submodule 'submodule_a' in it
     and a module 'egg2' with the same submodule, not initializing the submodule
@@ -482,7 +488,9 @@ def test_update_with_submodule_checkout(mkgitrepo, src, git_allow_file_protocol)
 @pytest.mark.skipif(
     condition=os.name == "nt", reason="submodules seem not to work on windows"
 )
-def test_update_with_submodule_dont_update_previous_submodules(mkgitrepo, src, git_allow_file_protocol):
+def test_update_with_submodule_dont_update_previous_submodules(
+    mkgitrepo, src, git_allow_file_protocol
+):
     """
     Tests the checkout of a module 'egg' with a submodule 'submodule_a' in it.
     Commits changes in the detached submodule, and checks update didn't break
diff --git a/src/mxdev/tests/utils.py b/src/mxdev/tests/utils.py
index 41adb48..5d34146 100644
--- a/src/mxdev/tests/utils.py
+++ b/src/mxdev/tests/utils.py
@@ -167,7 +167,7 @@ def add_file(self, fname, msg=None):
     def add_submodule(self, submodule: "GitRepo", submodule_name: str):
         assert isinstance(submodule, GitRepo)
         assert isinstance(submodule_name, str)
-             
+
         self(f"git submodule add {submodule.url}")
         self("git add .gitmodules")
         self(f"git add {submodule_name}")