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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_cc(self, cc, **kwargs):
 """ Applies contrast curve constraint to each population See :func:`vespa.stars.StarPopulation.apply_cc`; all arguments passed to that function for each population. """

        if type(cc)==type(''):
            pass
        if cc.name not in self.constraints:
            self.constraints.append(cc.name)
        for pop in self.poplist:
            if not pop.is_specific:
                try:
                    pop.apply_cc(cc, **kwargs)
                except AttributeError:
                    logging.info('%s cc not applied to %s model' % (cc.name,pop.model))