fix for doctest failure
fix for doctest failure

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