'Needs replace based on prop_diff.'

def needs_replace_with_prop_diff(self, changed_properties_set, after_props, before_props):

    if (self.FLAVOR in changed_properties_set):
        flavor_update_policy = (after_props.get(self.FLAVOR_UPDATE_POLICY) or before_props.get(self.FLAVOR_UPDATE_POLICY))
        if (flavor_update_policy == 'REPLACE'):
            return True
    if (self.IMAGE in changed_properties_set):
        image_update_policy = (after_props.get(self.IMAGE_UPDATE_POLICY) or before_props.get(self.IMAGE_UPDATE_POLICY))
        if (image_update_policy == 'REPLACE'):
            return True
    if (self.USER_DATA in changed_properties_set):
        ud_update_policy = (after_props.get(self.USER_DATA_UPDATE_POLICY) or before_props.get(self.USER_DATA_UPDATE_POLICY))
        return (ud_update_policy == 'REPLACE')
