title: Python Tkinter coords function not moving canvas objects inside loop
body: <p>I have a function that reads locations from a text file, parses them, then moves the respective objects to the locations listed on a tkinter canvas using the coords function.  The data is being read from the file and parsed correctly but for some reason the coords function is only moving the objects to the last location listed in the file on the last iteration of the loop.</p>
  
  <p>Do I need to update the canvas somehow after each iteration of my loop?  Thanks!</p>
  
  <p>Here is my code:</p>
  
  <pre><code>def playback():
      fptr = tkFileDialog.askopenfilename()
      filename = open(fptr,"rU")
      if not filename:
          return
  
      stat.set('REPLAY IN PROGRESS')
      gamestatus[0] = 2
      for line in filename:
          line = line.strip()
  
          #Example line from input file: 'B:#,#,#,#|L:#,#,#,#|R:#,#,#,#'
          line = line.split('|')
          B_loc = line[0].split(':')[1].split(',')
          L_loc = line[1].split(':')[1].split(',')
          R_loc = line[2].split(':')[1].split(',')
  
          #Converting strings to ints and lists to tuples to simplify code below      
          B_tup=(int(B_loc[0]),int(B_loc[1]),int(B_loc[2]),int(B_loc[3]))
          L_tup=(int(L_loc[0]),int(L_loc[1]),int(L_loc[2]),int(L_loc[3]))
          R_tup=(int(R_loc[0]),int(R_loc[1]),int(R_loc[2]),int(R_loc[3]))
  
          #Moving objects to locations from input file        
          playingField.coords(pongball.ball,B_tup)
          playingField.coords(leftpaddle.paddle,L_tup)
          playingField.coords(rightpaddle.paddle,R_tup)
          time.sleep(.02)
  
      filename.close()
      gamestatus[0] = 0
      stat.set('-------Pong-------')
  </code></pre>