wesley chun wrote: >> 3)is there a special method for `is'. > > no, not really. you can use id() and '==' to proxy for is: > > a is b <==> id(a) == id(b) No, not necessarily. id's are recycled which can lead to unexpected behaviour when comparing them. See for example this thread on c.l.py: http://tinyurl.com/yflknx Kent