Fix flake8 error.
Fix flake8 error.

Github's online editor is bad...
techtonik/pip,ChristopherHogan/pip,jythontools/pip,jasonkying/pip,prasaianooz/pip,nthall/pip,jamezpolley/pip,esc/pip,mindw/pip,msabramo/pip,davidovich/pip,nthall/pip,ianw/pip,harrisonfeng/pip,zorosteven/pip,ncoghlan/pip,benesch/pip,jamezpolley/pip,techtonik/pip,RonnyPfannschmidt/pip,ChristopherHogan/pip,ChristopherHogan/pip,chaoallsome/pip,pypa/pip,luzfcb/pip,Gabriel439/pip,Carreau/pip,zorosteven/pip,prasaianooz/pip,pradyunsg/pip,jasonkying/pip,natefoo/pip,KarelJakubec/pip,xavfernandez/pip,dstufft/pip,erikrose/pip,willingc/pip,KarelJakubec/pip,davidovich/pip,h4ck3rm1k3/pip,KarelJakubec/pip,Gabriel439/pip,zorosteven/pip,tdsmith/pip,graingert/pip,haridsv/pip,caosmo/pip,graingert/pip,zvezdan/pip,chaoallsome/pip,Gabriel439/pip,patricklaw/pip,wkeyword/pip,mujiansu/pip,tdsmith/pip,ncoghlan/pip,erikrose/pip,dstufft/pip,zvezdan/pip,h4ck3rm1k3/pip,jmagnusson/pip,habnabit/pip,alex/pip,jamezpolley/pip,haridsv/pip,luzfcb/pip,esc/pip,jasonkying/pip,atdaemon/pip,RonnyPfannschmidt/pip,alex/pip,techtonik/pip,wkeyword/pip,esc/pip,pjdelport/pip,alex/pip,pradyunsg/pip,yati-sagade/pip,graingert/pip,qbdsoft/pip,pfmoore/pip,pjdelport/pip,pypa/pip,willingc/pip,rbtcollins/pip,erikrose/pip,atdaemon/pip,fiber-space/pip,fiber-space/pip,cjerdonek/pip,blarghmatey/pip,harrisonfeng/pip,James-Firth/pip,wkeyword/pip,atdaemon/pip,cjerdonek/pip,jythontools/pip,RonnyPfannschmidt/pip,haridsv/pip,rouge8/pip,xavfernandez/pip,mujiansu/pip,mujiansu/pip,h4ck3rm1k3/pip,qbdsoft/pip,rouge8/pip,benesch/pip,sbidoul/pip,harrisonfeng/pip,blarghmatey/pip,James-Firth/pip,James-Firth/pip,patricklaw/pip,rbtcollins/pip,natefoo/pip,sigmavirus24/pip,squidsoup/pip,zvezdan/pip,dstufft/pip,yati-sagade/pip,Carreau/pip,caosmo/pip,nthall/pip,habnabit/pip,sbidoul/pip,xavfernandez/pip,zenlambda/pip,willingc/pip,mindw/pip,rouge8/pip,ncoghlan/pip,sigmavirus24/pip,jythontools/pip,benesch/pip,jmagnusson/pip,mattrobenolt/pip,davidovich/pip,rbtcollins/pip,squidsoup/pip,zenlambda/pip,pfmoore/pip,qbdsoft/pip,luzfcb/pip,pjdelport/pip,zenlambda/pip,supriyantomaftuh/pip,fiber-space/pip,sigmavirus24/pip,tdsmith/pip,msabramo/pip,habnabit/pip,squidsoup/pip,chaoallsome/pip,jmagnusson/pip,supriyantomaftuh/pip,caosmo/pip,blarghmatey/pip,mindw/pip,supriyantomaftuh/pip,natefoo/pip,ianw/pip,prasaianooz/pip,yati-sagade/pip,mattrobenolt/pip