def copy_instance_vars(self, space, w_other):
"""Copies special instance vars after #copy or #dup"""
assert isinstance(w_other, W_ExceptionObject)
W_Object.copy_instance_vars(self, space, w_other)
self.msg = w_other.msg
self.frame = w_other.frame
self.w_backtrace = w_other.w_backtrace
