title: python Tkinter label changing text value by Button Command
body: <p>I am using Tkinter Label widget to display some text to my UI Frame and I want the Label to change the text every-time I click the button. In my case I got wrong... it didn't change, is it possible?</p>
  
  <p>This is my code..</p>
  
  <pre><code>currentCounterNumber = "0"
  
  def counterPlus(teller_num):
      #.... the data is working well ....
      data = s.recv(1024) 
      if data:
          currentCounterNumber = data
  ......
  class Content(tk.Frame):
  def __init__(self, master, teller_name,*args, **kwargs):
      tk.Frame.__init__(self, *args, borderwidth=20, **kwargs)
      self.L4 = tk.Label(self, text="Serving # " + currentCounterNumber +"!")
      self.L4.pack( side = "top", fill="both", expand=False)      
  
      self.button1 = tk.Button(self, text="+", width=15, command=lambda: counterPlus(teller_no))
      self.button1.pack(side = "top", fill="both", expand=True)
  </code></pre>