old_contents: #/usr/bin/env python
  def my_sum(x, y):
      return x + y
  
  def my_sum2(x, y):
      return x + y
  
new_contents: #/usr/bin/env python
  def my_sum(x, y):
      return x + y
  
  def my_sum2(x, y):
      return x + y
  
  # To run method alone
  if __name__ == "__main__":
      import sys
      if len(sys.argv) != 3:
          print("%s str1 str2" % sys.argv[0])
          raise SystemExit(1)
  
      print(my_sum(sys.argv[1], sys.argv[2]))
  
  
  
subject: Test run a module alone