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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 apply_vcc(self, vcc, distribution_skip=False, **kwargs):
 """ Applies "velocity contrast curve" to population. That is, the constraint that comes from not seeing two sets of spectral lines in a high resolution spectrum. Only works if population has ``dmag`` and ``RV`` attributes. :param vcc: Velocity contrast curve; dmag vs. delta-RV. :type cc: :class:`VelocityContrastCurveConstraint` :param distribution_skip: This is by default ``True``. *To be honest, I'm not exactly sure why. Might be important, might not (don't remember).* :param **kwargs: Additional keyword arguments passed to :func:`StarPopulation.apply_constraint`. """

        rvs = self.RV.value
        dmags = self.dmag(vcc.band)
        self.apply_constraint(VelocityContrastCurveConstraint(rvs,dmags,vcc,
                                                              name='secondary spectrum'),
                              distribution_skip=distribution_skip, **kwargs)