Applies pep8 and pyflakes recommendations.
Applies pep8 and pyflakes recommendations.

White space tweaking.

semio/zipline,grundgruen/zipline,jordancheah/zipline,sketchytechky/zipline,CDSFinance/zipline,MonoCloud/zipline,enigmampc/catalyst,jordancheah/zipline,humdings/zipline,dhruvparamhans/zipline,ChinaQuants/zipline,ChinaQuants/zipline,kmather73/zipline,iamkingmaker/zipline,otmaneJai/Zipline,aajtodd/zipline,iamkingmaker/zipline,keir-rex/zipline,CarterBain/AlephNull,CDSFinance/zipline,semio/zipline,YuepengGuo/zipline,MonoCloud/zipline,gwulfs/zipline,alphaBenj/zipline,wilsonkichoi/zipline,chrjxj/zipline,bartosh/zipline,erikness/AlephOne,bartosh/zipline,dmitriz/zipline,DVegaCapital/zipline,chrjxj/zipline,DVegaCapital/zipline,euri10/zipline,davidastephens/zipline,wubr2000/zipline,umuzungu/zipline,wubr2000/zipline,YuepengGuo/zipline,zhoulingjun/zipline,jimgoo/zipline-fork,michaeljohnbennett/zipline,Scapogo/zipline,stkubr/zipline,cmorgan/zipline,AlirezaShahabi/zipline,ronalcc/zipline,florentchandelier/zipline,mattcaldwell/zipline,florentchandelier/zipline,quantopian/zipline,keir-rex/zipline,dhruvparamhans/zipline,mattcaldwell/zipline,quantopian/zipline,dmitriz/zipline,umuzungu/zipline,otmaneJai/Zipline,Scapogo/zipline,enigmampc/catalyst,davidastephens/zipline,humdings/zipline,dkushner/zipline,joequant/zipline,michaeljohnbennett/zipline,nborggren/zipline,joequant/zipline,StratsOn/zipline,sketchytechky/zipline,StratsOn/zipline,dkushner/zipline,magne-max/zipline-ja,kmather73/zipline,alphaBenj/zipline,jimgoo/zipline-fork,zhoulingjun/zipline,cmorgan/zipline,wilsonkichoi/zipline,morrisonwudi/zipline,erikness/AlephOne,AlirezaShahabi/zipline,grundgruen/zipline,gwulfs/zipline,stkubr/zipline,euri10/zipline,nborggren/zipline,morrisonwudi/zipline,magne-max/zipline-ja,ronalcc/zipline,aajtodd/zipline,CarterBain/AlephNull