[Zope] basis Zope/Python script question

Hello, I write the following code repeatedly: if request.has_key('v1'): v1=request.v1 else: v1=-1 if request.has_key('v2'): v2=request.v2 else: v2=-1 etc. Is there a way to do this more efficient and clean, something like this: for reqvar in ['v1','v2','v3']: if request.haskey(reqvar): reqvar=request.reqvar #this doesn't work else reqvar=-1 # and this also not. Het vriendelijke groeten, Hans de Wit Stichting Farmaceutische Kengetallen Postbus 30460 2500 GL DEN HAAG Tel. 070-3737448 Fax 070-3737445