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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 round_up(self, num):
 """Determine the length to use for this waveform by rounding. Parameters num : int Proposed size of waveform in seconds Returns ------- size: int The rounded size to use for the waveform buffer in seconds. This is calculaed using an internal `increment` attribute, which determines the discreteness of the rounding. """

        inc = self.increment
        size = np.ceil(num / self.sample_rate / inc) * self.sample_rate * inc
        return size