class_docstr: Used to decorate file-like objects with a handy 'writeln' method
code: def writeln(self, arg=None):
      if arg:
          self.write(arg)
      self.write("\n")
  
imports: import unittest
  import doctest
  import sys
  import time
  import timeside.core
label_desc: Use image node_id 3 for calling the _WritelnDecorator obj's underlying member method code with example usage: obj.writeln(arg) without return types