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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 _load_calib_rigid(self, filename):
 """Read a rigid transform calibration file as a numpy.array."""

        filepath = os.path.join(self.calib_path, filename)
        data = utils.read_calib_file(filepath)
        return utils.transform_from_rot_trans(data['R'], data['T'])