did the flake8 test on database init

navipy/database/__init__.py

@@ -466,7 +466,7 @@ database
         return toreturn
 
     def denormalise_image(self, image, cmaxminrange):
-        if not isinstance(image,np.ndarray):
+        if not isinstance(image, np.ndarray):
             raise TypeError('image must be np.array')
         if len(image.shape) != 3:
             raise Exception('image should be 3D array')