title: The way of using images in Tkinter as icons for best performance
body: <p>Currently I am creating tkinter GUI app and I am using some images as icons for items in treeview widget. In order to read and keep them as a reference I used this code:</p>
  
  <pre><code>self.logoadd = tk.PhotoImage(file='../img/add.png')
  self.logodel = tk.PhotoImage(file='../img/delete.png')
  ...
  self.logoedit = tk.PhotoImage(file='../img/edit.png')
  
  #Keep them as references
  self.imgAdd = self.logoadd
  self.imgDel = self.logodel
  ...
  self.imgEdit = self.logoedit
  </code></pre>
  
  <p>And I think this is not a good practice if there are more than 30 images used. Another approaches which came to my head are:</p>
  
  <ul>
  <li>to store images as a byte string in .py file or;</li>
  <li>using for loop to retrieve all images in folder pass them as variable.</li>
  </ul>
  
  <p>I need some advice from experienced GUI developers. Which way is the best in order to performance and used in GUI practices? (May be all of my ways are wrong)</p>
  
  <p><strong>For info:</strong> Size of these images is 16x16 and images used for file icons</p>