title: Python - Tkinter - Label Not Updating
body: <p>Any ideas why the leftresult_label label does not update? The function seems to work but the label does not update. I have looked everywhere and can't find an answer. The 'left' value gets set but the label does not change. </p>
  
  <pre><code>from tkinter import *
  
  root = Tk(className="Page Calculator")
  
  read = IntVar()
  
  total = IntVar()
  
  left = IntVar()
  
  read.set(1)
  
  total.set(1)
  
  left.set(1)
  
  read_label = Label(root,text="Pages Read:")
  read_label.grid(column=1, row=1)
  
  total_label = Label(root,text="Total Pages:")
  total_label.grid(column=1, row=2)
  
  read_entry = Entry(root,textvariable=read)
  read_entry.grid(column=2, row=1)
  
  total_entry = Entry(root,textvariable=total)
  total_entry.grid(column=2, row=2)
  
  def func1():
      left.set(total.get() - read.get())
      print(left.get())
  
  calculate_button = Button(root,text="Calculate",command= func1)
  calculate_button.grid(column=2, row=3)
  
  percenet_label = Label(root,text="Percent Finished:")
  percenet_label.grid(column=1, row=4)
  
  left_label = Label(root,text="Pages Left:")
  left_label.grid(column=1, row=5)
  
  percenetresult_label = Label(root,text=left.get())
  percenetresult_label.grid(column=2, row=4)
  
  leftresult_label = Label(root,text="")
  leftresult_label.grid(column=2, row=5)
  
  root.mainloop()
  </code></pre>