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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 _find_classes_param(self):
 """ Searches the wrapped model for the classes_ parameter. """

        for attr in ["classes_"]:
            try:
                return getattr(self.estimator, attr)
            except AttributeError:
                continue

        raise YellowbrickTypeError(
            "could not find classes_ param on {}".format(
                self.estimator.__class__.__name__
            )
        )