old_contents: 
  import sys
  
  # Update the path below to find the python version of the ANTLR4 runtime files.
  sys.path.append("../libs")
  
  from Python2Parser       import Python2Parser
  from Python2Lexer        import Python2Lexer
  from Python2ListenerImpl import Python2ListenerImpl
  from antlr4              import *
  
  def main(argv):
      input = FileStream("test_input_Python2Parser.py") #argv[1])
      lexer = Python2Lexer(input);
      tokens = CommonTokenStream(lexer);
      parser = Python2Parser(tokens);
      tree = parser.file_input(); 
  
      listener = Python2ListenerImpl(parser);
      ParseTreeWalker.DEFAULT.walk(listener, tree); 
      
  
  if __name__ == "__main__":
      main(sys.argv)
  
new_contents: 
  import sys
  
  # Update the path below to find the python version of the ANTLR4 runtime files.
  sys.path.append("../libs")
  
  from Python2Parser       import Python2Parser
  from Python2Lexer        import Python2Lexer
  from Python2Listener     import Python2Listener
  from antlr4              import *
  
  def main(argv):
      input  = FileStream("test_input_Python2Parser.py") #argv[1])
      lexer  = Python2Lexer(input);
      tokens = CommonTokenStream(lexer);
      parser = Python2Parser(tokens);
      tree   = parser.file_input(); 
  
      listener = Python2Listener(parser);
      ParseTreeWalker.DEFAULT.walk(listener, tree); 
      
  
  if __name__ == "__main__":
      main(sys.argv)
  
subject: Update main.py