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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 remove_zero_points(self):
 """Removes points with a zero in the z-axis. Note ---- This returns nothing and updates the PointCloud in-place. """

        points_of_interest = np.where(self.z_coords != 0.0)[0]
        self._data = self.data[:, points_of_interest]