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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 _update_mean_coords(self, dig, N, centers_sum, **paircoords):
 """ Update the mean coordinate sums """

        if N is None or centers_sum is None: return

        N.flat[:] += utils.bincount(dig, 1., minlength=N.size)
        for i, dim in enumerate(self.dims):
            size = centers_sum[i].size
            centers_sum[i].flat[:] += utils.bincount(dig, paircoords[dim], minlength=size)