title: Python Tkinter Letting Tk cover entire screen (like fullscreen)
body: <p>Is there a way to use tkinter's Tk() frame with a canvas in a way that it covers the entire screen but doesnt get bigger than the screen.
  I mean it shall be similar to fullscreen.
  If this is a part of my code:</p>
  
  <pre><code>class X:
      def __init__(self):
          self.tk = Tk()
          self.canvas = Canvas(self.tk, width=500, height=500, highlightthickness=0)
          self.canvas.pack()
  </code></pre>
  
  <p>How would I achieve this? I think it is something with:</p>
  
  <pre><code>self.canvas.attributes(width=x)
  </code></pre>
  
  <p>Also: How would I now how big the canvas currently is (considering I don't save it in a variable)? Is there some kind of method or attribute of Canvas I could access?</p>