what does this mean?

From: mr. ice (icemon999_at_yahoo.com)
Date: 05/19/04 

Date: 19 May 2004 09:30:36 -0700

I am new to python, The following statement is in the beginning of
class definition in a python scripts, what does it mean? Help?
class %(class_)s_W : public XMsg_W
{

icemon