diff --git a/skimage/filters/rank/__init__.py b/skimage/filters/rank/__init__.py
index 22b0e881..37b5f9cd 100644
--- a/skimage/filters/rank/__init__.py
+++ b/skimage/filters/rank/__init__.py
@@ -1,6 +1,7 @@
 from .generic import (autolevel, bottomhat, equalize, gradient, maximum, mean,
                       subtract_mean, median, minimum, modal, enhance_contrast,
-                      pop, threshold, tophat, noise_filter, entropy, otsu, sum, windowed_histogram)
+                      pop, threshold, tophat, noise_filter, entropy, otsu,
+                      sum, windowed_histogram)
 from ._percentile import (autolevel_percentile, gradient_percentile,
                           mean_percentile, subtract_mean_percentile,
                           enhance_contrast_percentile, percentile,