text: from typing import List
  from app.ml.objects.classification import Classifier
  from app.ml.objects.feature import Feature
  from app.ml.objects.imputation import Imputation
  from app.ml.objects.normalization import Normalization
  
  def get_features() -> List[Feature]:
      return [feature for feature in Feature]
  
  def get_imputations() -> List[Imputation]:
      return [imputation for imputation in Imputation]
  
  def get_normalizations() -> List[Normalization]:
      return [normalization for normalization in Normalization]
  
  def get_classifiers() -> List[Classifier]:
      return [classifier for classifier in Classifier]