old_contents: #!/usr/bin/env python
  # coding: UTF-8
  
  HOST = "localhost"
  USER = "root"
  PASSWORD = "csupeng"
  DB = "markov2tensor"
new_contents: #!/usr/bin/env python
  # coding: UTF-8
  
  HOST = "localhost"
  USER = "root"
  PASSWORD = "123456"
  DB = "markov2tensor"
  
subject: Update settings.py