code: def is_clusterer(estimator):
      """
      Returns True if the given estimator is a clusterer.
  
      Parameters
      ----------
      estimator : class or instance
          The object to test if it is a Scikit-Learn clusterer, especially a
          Scikit-Learn estimator or Yellowbrick visualizer
      """
  
      # Test the _estimator_type property
      return getattr(estimator, "_estimator_type", None) == "clusterer"
  
file_path: yellowbrick/yellowbrick/utils/types.py
imports: import inspect
  import numpy
  from sklearn.base import BaseEstimator
  from yellowbrick.contrib.wrapper import ContribEstimator
label_desc: Use image node_id 4 for calling a global function with example usage: is_clusterer(estimator) and returns: unknown