title: Connect to SFTP with key file using Python pysftp
body: <p>I need to connect to a SFTP, download the most recent file, then change the file name and load again to the same SFTP folder and delete the 'original name' file. I have done this with FTP with user and password, however in this case, the SFTP has a key file (.ppk). How can set the key file as password? </p>
  
  <p>Thank you!    </p>
  
  <pre><code>import pysftp
  
  srv = pysftp.Connection(host="your_FTP_server", username="your_username",
  password="your_password")
  
  # Get the directory and file listing
  data = srv.listdir()
  
  # Closes the connection
  srv.close()
  
  # Prints out the directories and files, line by line
  for i in data:
     print i
  </code></pre>