Sets the policy of the given item

def setItemPolicy(self, item, policy):
        """Sets the policy of the given item"""
        index = item._combobox_indices[self.ColAction].get(policy, 0)
        self._updateItemComboBoxIndex(item, self.ColAction, index)
        combobox = self.itemWidget(item, self.ColAction)
        if combobox:
            combobox.setCurrentIndex(index)