code: def apply_multicolor_transit(self,band,depth):
          
          if '{} band transit'.format(band) not in self.constraints:
              self.constraints.append('{} band transit'.format(band))
          for pop in self.poplist:
              pop.apply_multicolor_transit(band,depth)
docs: Applies constraint corresponding to measuring transit in different band
  
          This is not implemented yet.