clean all pep8 warnings
clean all pep8 warnings

ThiefMaster/sqlalchemy,davidjb/sqlalchemy,hsum/sqlalchemy,EvaSDK/sqlalchemy,olemis/sqlalchemy,itkovian/sqlalchemy,inspirehep/sqlalchemy,wfxiang08/sqlalchemy,alex/sqlalchemy,inspirehep/sqlalchemy,pdufour/sqlalchemy,halfcrazy/sqlalchemy,Cito/sqlalchemy,Cito/sqlalchemy,bdupharm/sqlalchemy,j5int/sqlalchemy,olemis/sqlalchemy,graingert/sqlalchemy,alex/sqlalchemy,monetate/sqlalchemy,Cito/sqlalchemy,pdufour/sqlalchemy,hsum/sqlalchemy,wujuguang/sqlalchemy,sandan/sqlalchemy,davidfraser/sqlalchemy,EvaSDK/sqlalchemy,WinterNis/sqlalchemy,alex/sqlalchemy,bootandy/sqlalchemy,robin900/sqlalchemy,dstufft/sqlalchemy,graingert/sqlalchemy,davidfraser/sqlalchemy,epa/sqlalchemy,276361270/sqlalchemy,bdupharm/sqlalchemy,WinterNis/sqlalchemy,wujuguang/sqlalchemy,brianv0/sqlalchemy,sandan/sqlalchemy,zzzeek/sqlalchemy,epa/sqlalchemy,wfxiang08/sqlalchemy,j5int/sqlalchemy,elelianghh/sqlalchemy,robin900/sqlalchemy,Akrog/sqlalchemy,276361270/sqlalchemy,ThiefMaster/sqlalchemy,monetate/sqlalchemy,dstufft/sqlalchemy,davidjb/sqlalchemy,sqlalchemy/sqlalchemy,itkovian/sqlalchemy,halfcrazy/sqlalchemy,bootandy/sqlalchemy,Akrog/sqlalchemy,elelianghh/sqlalchemy,brianv0/sqlalchemy