code: def _update_class(self, oldclass, newclass):
          
          olddict = oldclass.__dict__
          newdict = newclass.__dict__
  
          oldnames = set(olddict)
          newnames = set(newdict)
  
          for name in newnames - oldnames:
              setattr(oldclass, name, newdict[name])
              notify_info0('Added:', name, 'to', oldclass)
              self.found_change = True
  
          # Note: not removing old things...
          # for name in oldnames - newnames:
          #    notify_info('Removed:', name, 'from', oldclass)
          #    delattr(oldclass, name)
  
          for name in (oldnames & newnames) - set(['__dict__', '__doc__']):
              self._update(oldclass, name, olddict[name], newdict[name], is_class_namespace=True)
  
          old_bases = getattr(oldclass, '__bases__', None)
          new_bases = getattr(newclass, '__bases__', None)
          if str(old_bases) != str(new_bases):
              notify_error('Changing the hierarchy of a class is not supported. %s may be inconsistent.' % (oldclass,))
  
          self._handle_namespace(oldclass, is_class_namespace=True)
docs: Update a class object.