old_contents: #!/usr/bin/python3
  
  import sys
  
  
  def version(prog):
      print(prog, "0.0.1")
  
  
  def opterr(prog, wrngopt):
      print("%s: invalid option --\'%s\'" % (prog, wrngopt.opt), file=sys.stderr)
      print("Try \'%s --help\' for more information." % (prog), file=sys.stderr)
      exit(-1)
  
new_contents: import sys
  
  
  def version(prog):
      print(prog, "0.0.1")
  
  
  def opterr(prog, wrngopt):
      print("%s: invalid option --\'%s\'" % (prog, wrngopt.opt), file=sys.stderr)
      print("Try \'%s --help\' for more information." % (prog), file=sys.stderr)
      exit(-1)
  
subject: remove the execute permission of common.py