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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):
 """ Applies velocity contrast curve constraint to each population See :func:`vespa.stars.StarPopulation.apply_vcc`; all arguments passed to that function for each population. """

        if 'secondary spectrum' not in self.constraints:
            self.constraints.append('secondary spectrum')
        for pop in self.poplist:
            if not pop.is_specific:
                try:
                    pop.apply_vcc(vcc)
                except:
                    logging.info('VCC constraint not applied to %s model' % (pop.model))