possible fix to cascade_mappers
possible fix to cascade_mappers

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