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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 _l_cv_and_skew(self, catchment):
 """ Calculate L-CV and L-SKEW for a gauged catchment. Uses `lmoments3` library. Methodology source: Science Report SC050050, para. 6.7.5 """

        z = self._dimensionless_flows(catchment)
        l1, l2, t3 = lm.lmom_ratios(z, nmom=3)
        return l2 / l1, t3