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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 bool(self):
 """ Return the bool of a single element PandasObject. This must be a boolean scalar value, either True or False. Raise a ValueError if the PandasObject does not have exactly 1 element, or that element is not boolean """

        v = self.squeeze()
        if isinstance(v, (bool, np.bool_)):
            return bool(v)
        elif is_scalar(v):
            raise ValueError("bool cannot act on a non-boolean single element "
                             "{0}".format(self.__class__.__name__))

        self.__nonzero__()