code: def constrain_property(self,prop,**kwargs):
          
          if prop not in self.constraints:
              self.constraints.append(prop)
          for pop in self.poplist:
              try:
                  pop.constrain_property(prop,**kwargs)
              except AttributeError:
                  logging.info('%s model does not have property stars.%s (constraint not applied)' % (pop.model,prop))
docs: Constrains property for each population
  
          See :func:`vespa.stars.StarPopulation.constrain_property`;
          all arguments passed to that function for each population.