diff --git a/skimage/exposure/exposure.py b/skimage/exposure/exposure.py
index 3a2accbc..1b42ecf8 100644
--- a/skimage/exposure/exposure.py
+++ b/skimage/exposure/exposure.py
@@ -3,6 +3,7 @@ import numpy as np
 
 from skimage import img_as_float
 from skimage.util.dtype import dtype_range, dtype_limits
+from skimage._shared.utils import deprecation_warning
 
 
 __all__ = ['histogram', 'cumulative_distribution', 'equalize',