code: def handler(self, ctx, str):
      self.lock.acquire()
      self.errors.append(str)
      self.lock.release()
  
imports: import string, sys, time
  from threading import Thread, Lock
  import libxml2
label_desc: Use image node_id 2 for calling the ErrorHandler obj's underlying member method code with example usage: obj.handler(ctx, str) without return types