title: Using Tkinter in Python Label does not recognize anchor=CENTER
body: <p>I am new to tkinter and have been using:</p>
  
  <pre><code>from tkinter import * 
  </code></pre>
  
  <p>but have read this is bad practice. 
  I rewrote a very small bit of code to start using the following:</p>
  
  <pre><code>import tkinter as tk
  </code></pre>
  
  <p>However when I run the rest of the code. I get the error:
  <code>label.place(relx=0.4, rely=0.35, anchor=CENTER)
  NameError: name 'CENTER' is not defined</code></p>
  
  <pre><code>root = tk.Tk()
  label = tk.Label(root, text="I am a label widget")
  label.place(relx=0.4, rely=0.35, anchor=CENTER)    
  button = tk.Button(root, text="I am a button")
  label.pack()
  button.pack()
  root.mainloop()
  </code></pre>
  
  <p>Is this a namespace issue? How can I solve the problem?</p>