Factor out  determination and allow specification in args
Factor out  determination and allow specification in args

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