diff --git a/src/napari_matplotlib/histogram.py b/src/napari_matplotlib/histogram.py
index cf677bea..0a49dc41 100644
--- a/src/napari_matplotlib/histogram.py
+++ b/src/napari_matplotlib/histogram.py
@@ -162,7 +162,6 @@ def on_update_layers(self) -> None:
 
     def draw(self) -> None:
         """Clear the axes and histogram the currently selected layer/slice."""
-
         # get the colormap from the layer depending on its type
         if isinstance(self.layers[0], napari.layers.Points):
             colormap = self.layers[0].face_colormap
@@ -183,16 +182,18 @@ def draw(self) -> None:
         if data is None:
             return
 
-        _, bins, patches = self.axes.hist(data, bins=50, edgecolor="white", linewidth=0.3)
+        _, bins, patches = self.axes.hist(
+            data, bins=50, edgecolor="white", linewidth=0.3
+        )
 
         # recolor the histogram plot
         if colormap is not None:
-            self.bins_norm = (bins - bins.min())/(bins.max() - bins.min())
+            self.bins_norm = (bins - bins.min()) / (bins.max() - bins.min())
             colors = colormap.map(self.bins_norm)
 
             # Set histogram style:
             for idx, patch in enumerate(patches):
-                patch.set_facecolor(colors[idx])        
+                patch.set_facecolor(colors[idx])
 
         # set ax labels
         self.axes.set_xlabel(x_axis_name)
diff --git a/src/napari_matplotlib/tests/test_histogram.py b/src/napari_matplotlib/tests/test_histogram.py
index 534d7952..e71fea2a 100644
--- a/src/napari_matplotlib/tests/test_histogram.py
+++ b/src/napari_matplotlib/tests/test_histogram.py
@@ -36,7 +36,6 @@ def test_histogram_3D(make_napari_viewer, brain_data):
 
 
 def test_feature_histogram(make_napari_viewer):
-
     n_points = 1000
     random_points = np.random.random((n_points, 3)) * 10
     random_directions = np.random.random((n_points, 3)) * 10
@@ -74,7 +73,6 @@ def test_feature_histogram(make_napari_viewer):
 
 @pytest.mark.mpl_image_compare
 def test_feature_histogram_vectors(make_napari_viewer):
-
     n_points = 1000
     np.random.seed(42)
     random_points = np.random.random((n_points, 3)) * 10
@@ -99,7 +97,6 @@ def test_feature_histogram_vectors(make_napari_viewer):
 
 @pytest.mark.mpl_image_compare
 def test_feature_histogram_points(make_napari_viewer):
-
     np.random.seed(0)
     n_points = 1000
     random_points = np.random.random((n_points, 3)) * 10
@@ -143,6 +140,7 @@ def test_change_layer(make_napari_viewer, brain_data, astronaut_data):
     assert_figures_not_equal(widget.figure, fig1)
 
 
-if __name__ == '__main__':
+if __name__ == "__main__":
     import napari
-    test_feature_histogram_points(napari.Viewer)
\ No newline at end of file
+
+    test_feature_histogram_points(napari.Viewer)