old_contents: #!/usr/bin/env python
  # coding: utf-8
  
  """Python snippet
  """
  
  import os
  import sys
  
  if __name__ == '__main__':
      if len (sys.argv) == 1:
          print ("Hi there!")
      else:
          print ("Hello, %s!" % sys.argv[1])
  
new_contents: #!/usr/bin/env python
  # coding: utf-8
  
  """Python snippet
  """
  
  import os
  import sys
  
  if __name__ == '__main__':
      if len (sys.argv) == 1:
          print ("Hi there!")
      elif len (sys.argv) == 2:
          print ("Hello, %s!" % sys.argv[1])
      else:
          print ("Usage: [python] %s nickname" % sys.argv[0])
  
subject: Revise Python snippet.