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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 pad_to_multiple(self, factor):
 """ Pad the pianoroll with zeros at the end along the time axis with the minimum length that makes the resulting pianoroll length a multiple of `factor`. Parameters factor : int The value which the length of the resulting pianoroll will be a multiple of. """

        remainder = self.pianoroll.shape[0] % factor
        if remainder:
            pad_width = ((0, (factor - remainder)), (0, 0))
            self.pianoroll = np.pad(self.pianoroll, pad_width, 'constant')