use copy.deepcopy() in _guess kwargs update for things w/o .copy() method
use copy.deepcopy() in _guess kwargs update for things w/o .copy() method

larrybradley/astropy,MSeifert04/astropy,StuartLittlefair/astropy,mhvk/astropy,astropy/astropy,StuartLittlefair/astropy,bsipocz/astropy,saimn/astropy,astropy/astropy,dhomeier/astropy,dhomeier/astropy,pllim/astropy,StuartLittlefair/astropy,dhomeier/astropy,MSeifert04/astropy,dhomeier/astropy,stargaser/astropy,stargaser/astropy,astropy/astropy,saimn/astropy,aleksandr-bakanov/astropy,dhomeier/astropy,mhvk/astropy,larrybradley/astropy,pllim/astropy,lpsinger/astropy,stargaser/astropy,lpsinger/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,StuartLittlefair/astropy,astropy/astropy,mhvk/astropy,bsipocz/astropy,saimn/astropy,lpsinger/astropy,pllim/astropy,pllim/astropy,stargaser/astropy,astropy/astropy,saimn/astropy,StuartLittlefair/astropy,saimn/astropy,mhvk/astropy,larrybradley/astropy,pllim/astropy,aleksandr-bakanov/astropy,lpsinger/astropy,larrybradley/astropy,aleksandr-bakanov/astropy,MSeifert04/astropy,bsipocz/astropy,lpsinger/astropy,MSeifert04/astropy,bsipocz/astropy,mhvk/astropy