Bugfix

nabu/io/reader.py

@@ -387,7 +387,7 @@ class ChunkReader(object):
         self.binning = binning
         binning_function = get_binning_function(binning[::-1]) # user provides (binning_x, binning_y)
         if binning_function is None:
-            raise NotImplementedError("Binning factor %s is not implemented yet" % binning)
+            raise NotImplementedError("Binning factor %s is not implemented yet" % str(binning))
         self.binning_function = binning_function