old_contents: #! /usr/bin/env python
  import os.path
  import time
  from time import strftime
  import os
  import sys
  import shutil
  
  FILE = 'todo.md'
  
  def date_to_append():
      return strftime("%m-%d-%Y", time.gmtime(os.path.getctime(FILE)))
  
  def rename_file(the_file):
      base = os.path.basename(the_file)
      split_up = os.path.splitext(base)
      file_name = os.path.splitext(base)[0]
      file_extension = split_up[1]
      new_file_name = "%s%s%s" % (file_name, date_to_append(), file_extension)
      os.rename(the_file, new_file_name)
  
  def move_old_todo():
      for filename in os.listdir("."):
          if filename.startswith('todo'):
              shutil.move(filename, 'Archive')
  
  def create_new_todo():
      open(FILE, 'w')
  
  rename_file(FILE)
  move_old_todo()
  create_new_todo()
  
new_contents: #! /usr/bin/env python
  import os.path
  import time
  from time import strftime
  import os
  import sys
  import shutil
  
  FILE = 'todo.md'
  
  def date_to_append():
      return strftime("%m-%d-%Y", time.gmtime(os.path.getctime(FILE)))
  
  def rename_file(the_file):
      base = os.path.basename(the_file)
      split_up = os.path.splitext(base)
      file_name = split_up[0]
      file_extension = split_up[1]
      new_file_name = "%s%s%s" % (file_name, date_to_append(), file_extension)
      os.rename(the_file, new_file_name)
  
  def move_old_todo():
      for filename in os.listdir("."):
          if filename.startswith('todo'):
              shutil.move(filename, 'Archive')
  
  def create_new_todo():
      open(FILE, 'w')
  
  rename_file(FILE)
  move_old_todo()
  create_new_todo()
  
subject: Use split_up in both places