[processing] Fix exception in IDW interpolation

nyalldawson · nyalldawson · commit c24f51ece807 · 2019-03-15T08:38:01.000+10:00
Fixes #21578
diff --git a/python/plugins/processing/algs/qgis/ui/InterpolationWidgets.py b/python/plugins/processing/algs/qgis/ui/InterpolationWidgets.py
@@ -30,20 +30,18 @@
 from qgis.PyQt import uic
 from qgis.PyQt.QtCore import pyqtSignal
 from qgis.PyQt.QtWidgets import (QTreeWidgetItem,
-                                 QComboBox
-                                 )
+                                 QComboBox)
 from qgis.core import (QgsApplication,
-                       QgsMapLayer,
                        QgsMapLayerProxyModel,
                        QgsWkbTypes,
                        QgsRectangle,
                        QgsReferencedRectangle,
                        QgsCoordinateReferenceSystem,
                        QgsProcessingUtils,
                        QgsProcessingParameterNumber,
-                       QgsProcessingParameterDefinition
-                       )
-from qgis.core import QgsFieldProxyModel
+                       QgsProcessingParameterDefinition,
+                       QgsFieldProxyModel)
+from qgis.gui import QgsDoubleSpinBox
 from qgis.analysis import QgsInterpolator
 
 from processing.gui.wrappers import WidgetWrapper, DIALOG_STANDARD
