def __str__(self, prefix="", printElemNumber=0):
    text = ""
    for (type_id, item) in self.items.items():
      if item.message_class is None:
        text += "%s[%d] <\n" % (prefix, type_id)
        text += "%s  (%d bytes)\n" % (prefix, len(item.message))
        text += "%s>\n" % prefix
      else:
        text += (prefix, item.message_class.__name__) % "%s[%s] <\n"
        text += item.message.__str__(prefix + "  ", printElemNumber)
        text += "%s>\n" % prefix
    return text
dataset/ETHPy150Open AppScale/appscale/AppServer/google/net/proto/message_set.py/MessageSet.__str__/swapped operands of `%`