fixed pep8 statndards in achivements/models
fixed pep8 statndards in achivements/models

akshayharidas/fosswebsite,akshayharidas/fosswebsite,rahulk98/fosswebsite,amfoss/fosswebsite,akshayharidas/fosswebsite,rahulk98/fosswebsite,akshaya9/fosswebsite,akshaya9/fosswebsite,manikishan/fosswebsite,rahulk98/fosswebsite,akshaya9/fosswebsite,navisk13/fosswebsite,Sparker0i/fosswebsite,csriharsha/fosswebsite,Sparker0i/fosswebsite,manikishan/fosswebsite,amfoss/fosswebsite,amfoss/fosswebsite,csriharsha/fosswebsite,csriharsha/fosswebsite,navisk13/fosswebsite,Sparker0i/fosswebsite,navisk13/fosswebsite,manikishan/fosswebsite