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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_binarized(self):
 """ Return True if the pianoroll is already binarized. Otherwise, return False. Returns ------- is_binarized : bool True if the pianoroll is already binarized; otherwise, False. """

        is_binarized = np.issubdtype(self.pianoroll.dtype, np.bool_)
        return is_binarized