code: def select_default_missing_value_policy(model, action):
      from .classifier.boosted_trees_classifier import (
          BoostedTreesClassifier,
      )
      from .classifier.random_forest_classifier import (
          RandomForestClassifier,
      )
      from .classifier.decision_tree_classifier import (
          DecisionTreeClassifier,
      )
      from .regression.boosted_trees_regression import (
          BoostedTreesRegression,
      )
      from .regression.random_forest_regression import (
          RandomForestRegression,
      )
      from .regression.decision_tree_regression import (
          DecisionTreeRegression,
      )
  
      tree_models = [
          BoostedTreesClassifier,
          BoostedTreesRegression,
          RandomForestClassifier,
          RandomForestRegression,
          DecisionTreeClassifier,
          DecisionTreeRegression,
      ]
  
      if any(
          isinstance(model, tree_model) for tree_model in tree_models
      ):
          return "none"
      else:
          return "impute"
  
imports: from __future__ import print_function
  from __future__ import division
  from __future__ import absolute_import
  import turicreate
  from turicreate.toolkits._model import Model
  from turicreate.toolkits._internal_utils import _raise_error_if_not_sframe
  from turicreate.toolkits._internal_utils import _validate_data
  from turicreate.toolkits._main import ToolkitError
  from turicreate._cython.cy_server import QuietProgress
label_desc: Use image node_id 6 for calling a global function with example usage: select_default_missing_value_policy(model, action) and returns: str, str