Fixed doctest to work on Python 2.6
Fixed doctest to work on Python 2.6

AustereCuriosity/astropy,saimn/astropy,tbabej/astropy,bsipocz/astropy,DougBurke/astropy,StuartLittlefair/astropy,bsipocz/astropy,MSeifert04/astropy,saimn/astropy,dhomeier/astropy,stargaser/astropy,kelle/astropy,saimn/astropy,MSeifert04/astropy,tbabej/astropy,pllim/astropy,MSeifert04/astropy,stargaser/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,bsipocz/astropy,saimn/astropy,dhomeier/astropy,larrybradley/astropy,kelle/astropy,astropy/astropy,lpsinger/astropy,pllim/astropy,joergdietrich/astropy,pllim/astropy,DougBurke/astropy,aleksandr-bakanov/astropy,tbabej/astropy,aleksandr-bakanov/astropy,DougBurke/astropy,lpsinger/astropy,AustereCuriosity/astropy,stargaser/astropy,pllim/astropy,DougBurke/astropy,joergdietrich/astropy,astropy/astropy,larrybradley/astropy,kelle/astropy,larrybradley/astropy,tbabej/astropy,lpsinger/astropy,mhvk/astropy,AustereCuriosity/astropy,lpsinger/astropy,dhomeier/astropy,pllim/astropy,joergdietrich/astropy,kelle/astropy,mhvk/astropy,astropy/astropy,astropy/astropy,astropy/astropy,StuartLittlefair/astropy,kelle/astropy,aleksandr-bakanov/astropy,larrybradley/astropy,dhomeier/astropy,StuartLittlefair/astropy,tbabej/astropy,saimn/astropy,AustereCuriosity/astropy,mhvk/astropy,funbaker/astropy,mhvk/astropy,AustereCuriosity/astropy,stargaser/astropy,funbaker/astropy,bsipocz/astropy,larrybradley/astropy,funbaker/astropy,joergdietrich/astropy,funbaker/astropy,lpsinger/astropy,mhvk/astropy,dhomeier/astropy,aleksandr-bakanov/astropy,joergdietrich/astropy,MSeifert04/astropy