class_docstr: server protocol. Methods from classes that subclass Server can be called
  transparently from a client
class_docstr_tok: ["server","protocol",".","Methods","from","classes","that","subclass","Server","can","be","called","transparently","from","a","client"]
code: def log(self, s):
      self.logf.write("Sever log %s: %s\n" % (self.log_prefix, s))
  
imports: import os
  import pickle
  import sys
  import _thread
  import traceback
  import socket
  import logging
label_desc: Use image node_id 2 for calling the Server obj's underlying member method code with example usage: obj.log(s) without return types