code: def is_sklearn_transformer(obj):
      """Check whether obj is an sklearn transformer.
  
      Parameters
      ----------
      obj : any object
  
      Returns
      -------
      bool, whether obj is an sklearn transformer
      """
      return (
          is_sklearn_estimator(obj)
          and sklearn_scitype(obj) == "transformer"
      )
  
file_path: sktime/sktime/utils/sklearn/_scitype.py
imports: from inspect import isclass
  from sklearn.base import BaseEstimator
  from sklearn.base import ClassifierMixin, ClusterMixin, RegressorMixin, TransformerMixin
  from sklearn.model_selection import GridSearchCV, RandomizedSearchCV
  from sklearn.pipeline import Pipeline
  from sktime.base import BaseObject
label_desc: Use image node_id 3 for calling a global function with example usage: is_sklearn_transformer(obj) and returns: unknown