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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 roundup(self, minimum_distance):
 """ If the minimum_distance is nonzero, returns a copy of the DistancesContext with updated distances, i.e. the ones below minimum_distance are rounded up to the minimum_distance. Otherwise, returns the original DistancesContext unchanged. """

        if not minimum_distance:
            return self
        ctx = DistancesContext()
        for dist, array in vars(self).items():
            small_distances = array < minimum_distance
            if small_distances.any():
                array = array[:]  # make a copy first
                array[small_distances] = minimum_distance
            setattr(ctx, dist, array)
        return ctx