add docstring for remove [ticket:1715]
add docstring for remove [ticket:1715]

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