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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 rvs(self, size=1, iteration=1):
 """Sample the random variable, using the preallocated samples if possible. Parameters size : int The number of samples to generate. iteration : int The location in the preallocated sample array to start sampling from. Returns ------- :obj:`numpy.ndarray` of float or int The samples of the random variable. If `size == 1`, then the returned value will not be wrapped in an array. """

        if self.num_prealloc_samples_ > 0:
            samples = []
            for i in range(size):
                samples.append(self.prealloc_samples_[(iteration + i) % self.num_prealloc_samples_])
            if size == 1:
                return samples[0]
            return samples
        # generate a new sample
        return self.sample(size=size)