diff --git a/pingouin/pairwise.py b/pingouin/pairwise.py
index 8549939d..5eca98dd 100644
--- a/pingouin/pairwise.py
+++ b/pingouin/pairwise.py
@@ -604,7 +604,7 @@ def ptests(
     padjust=None,
     stars=True,
     pval_stars={0.001: "***", 0.01: "**", 0.05: "*"},
-    **kwargs
+    **kwargs,
 ):
     """
     Pairwise T-test between columns of a dataframe.
diff --git a/pyproject.toml b/pyproject.toml
index 037585e8..67a6d04a 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -1,2 +1,4 @@
 [tool.black]
-line-length = 100
\ No newline at end of file
+line-length = 100
+target-version = ['py311']
+include = '\.pyi?$'
\ No newline at end of file