Fix: potential NameError bug in test case.
Fix: potential NameError bug in test case.

ProgressivePlanning/mongoengine,prijindal/mongoengine,cogniteev/mongoengine,iandd0824/mongoengine,MRigal/mongoengine,khallaghi/mongoengine,elephanter/mongoengine,ContextLogic/mongoengine,RussellLuo/mongoengine,nathanial/mongoengine,cogniteev/mongoengine,closeio/mongoengine,newvem/mongoengine,conversocial/mongoengine,WingGao/mongoengine,Davidrjx/mongoengine,KarimAllah/mongoengine,hmarr/mongoengine,losintikfos/mongoengine,ms5/mongoengine,Multiposting/mongoengine,muhammad-ammar/mongoengine,sourcelair/mongoengine,larsbutler/mongoengine,DavidBord/mongoengine,gmacon/mongoengine,eli-b/mongoengine,MakerReduxCorp/mongoengine,colinhowe/mongoengine,nicolascine/mongoengine,blaggacao/mongoengine,starsirius/mongoengine,depop/mongoengine-stripped,Catstyle/mongoengine,9nix00/mongoengine,reallistic/mongoengine,ContextLogic/mongoengine,jimmyshen/mongoengine,Davidrjx/mongoengine,ConsumerPhysics/mongoengine,gavincabbage/mongoengine,touilleMan/mongoengine,MakerReduxCorp/mongoengine,aszwemin/mongoengine,MongoEngine/mongoengine,noirbizarre/mongoengine,yarneo/mongoengine