title: Python Tkinter remove/delete Image from Label
body: <p>I have a label with an image, and a button which should update the label / delete the image in the label, so I can put a new image into the same label via label.config.</p>
  
  <p>I tryed to use something like that: whenever you click on the button the it should remove the image with label.config(image = None) but it doesnt work, if I load new images into the label the old ones are still there:</p>
  
  <pre><code>    # here is the label initialized 
      global brand_preview
      brand_preview = Label(root, image = None)
      brand_preview.place(x = 10, y = 60)
  
      # thats the button which have to clear the label image
      self.top_brand = Button(root, text = "clear", bg = "snow3", command=clear_label_image)
      self.top_brand.place(x = 550, y = 60)
  
      # thats how I load a photoimage into the label
      photoimg_brand = ImageTk.PhotoImage(im_thumb)
      brand_preview.image = photoimg_brand
      brand_preview.config(image = photoimg_brand)
  
      # Thats how the button works
      def clear_label_image():
          brand_preview.config(image = None)
          brand_preview.image = None
  </code></pre>
  
  <p>All I want now that if we I click the Button the brand_preview loses the image / the image gets deleted</p>
  
  <p>EDIT:
  The main issue is solved, but that only works if the button only has to delete the image. If I want to delete and add a new one it doesnt work</p>
  
  <pre><code>def clear_label_image():
      brand_preview.config(image = "")
      photoimg_brand = ImageTk.PhotoImage(im_thumb)
      brand_preview.image = photoimg_brand
      brand_preview.config(image = photoimg_brand)
  </code></pre>