diff --git a/viz.py b/viz.py
index a5a0d078..9ee9b8b6 100644
--- a/viz.py
+++ b/viz.py
@@ -5,25 +5,31 @@
 import pytest
 from mesa.visualization import SolaraViz
 
+
 def get_viz_files(directory):
     viz_files = []
     for root, dirs, files in os.walk(directory):
         for file in files:
-            if file in ['app.py', 'viz.py']:
+            if file in ["app.py", "viz.py"]:
                 module_name = os.path.relpath(os.path.join(root, file[:-3])).replace(
                     os.sep, "."
                 )
                 viz_files.append(module_name)
     return viz_files
 
+
 @pytest.mark.parametrize("module_name", get_viz_files("examples"))
 def test_solara_viz(module_name):
     # Add the 'examples' directory to the Python path
-    examples_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), '..', 'examples'))
+    examples_dir = os.path.abspath(
+        os.path.join(os.path.dirname(__file__), "..", "examples")
+    )
     sys.path.insert(0, examples_dir)
 
     # Add the parent directory of the module to the Python path
-    module_parent_dir = os.path.abspath(os.path.join(examples_dir, os.path.dirname(module_name.replace('.', os.sep))))
+    module_parent_dir = os.path.abspath(
+        os.path.join(examples_dir, os.path.dirname(module_name.replace(".", os.sep)))
+    )
     if module_parent_dir not in sys.path:
         sys.path.insert(0, module_parent_dir)
 
@@ -83,6 +89,7 @@ def test_solara_viz(module_name):
     if module_parent_dir in sys.path:
         sys.path.remove(module_parent_dir)
 
+
 # Run the tests
 if __name__ == "__main__":
     pytest.main([__file__, "-v"])