[processing] fix Number of unique values in classes alg (fix #12731)

alexbruy · alexbruy · commit b16b87427a97 · 2015-05-20T11:47:03.000+03:00
diff --git a/python/plugins/processing/algs/qgis/scripts/Number_of_unique_values_in_classes.py b/python/plugins/processing/algs/qgis/scripts/Number_of_unique_values_in_classes.py
@@ -4,6 +4,10 @@
 ##value_field=field input
 ##output=output vector
 
+from PyQt4.Qt import QVariant
+
+from qgis.core import QgsField, QgsFeature
+
 layer = processing.getObject(input)
 provider = layer.dataProvider()
 fields = provider.fields()
