def group_by_object(stream):
 stream = iter(stream)
 current = next(stream)
 current_key = (current.cls, current.id)
 group = [current]
 for message in stream:
  if ((message.cls, message.id) != current_key):
   (yield (current_key, group))
   group = []
  group.append(message)
  current = message
  current_key = (current.cls, current.id)
 (yield (current_key, group))

def group_by_object ( stream ) : stream = iter ( stream ) current = next ( stream ) current_key = ( current . cls , current . id ) group = [ current ] for message in stream : if ( ( message . cls , message . id ) != current_key ) : ( yield ( current_key , group ) ) group = [ ] group . append ( message ) current = message current_key = ( current . cls , current . id ) ( yield ( current_key , group ) )
group stream by object yields ( .