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

def is_gridsearch(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
    """

    from sklearn.model_selection import GridSearchCV, RandomizedSearchCV

    if inspect.isclass(estimator):
        return issubclass(estimator, (GridSearchCV, RandomizedSearchCV))

    return isinstance(estimator, (GridSearchCV, RandomizedSearchCV))