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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 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))