title: TypeError: login() missing 2 required positional arguments: 'username' and 'password'
body: <p>I have the code below:</p>
  
  <pre><code>from tkinter import *
  from customer import Customer
  from admin import Admin
  from account import Account
  from tkinter import ttk
  root = Tk()
  
  global username
  global password
  
  
  def login(self, username, password):
      name = username.get()
      passphrase = password.get()
      msg = self.customer_login(name, passphrase)
  
  
  
  
  root.config(height=500, width=500)
  frame = Frame(root)
  Label(root, text="Login").grid(row=0, columnspan=4)
  
  Label(root, text="Username").grid(row=3, sticky=W, padx=4)
  username = Entry(root).grid(row=3, column=2, sticky=W, pady=4)
  Label(root, text="Password").grid(row=4, sticky=W, padx=4,)
  password = Entry(root, show="*").grid(row=4, column=2, sticky=W, pady=4)
  
  loginButton = Button(root, text="Login", width=40)
  loginButton.grid(row=5, columnspan=4, pady=4, padx=4)
  loginButton.bind("&lt;Button-1&gt;", login)
  
  
  root.mainloop()
  </code></pre>
  
  <p>The error I keep getting is:</p>
  
  <pre><code>Exception in Tkinter callback
  Traceback (most recent call last):
    File "C:\Python34\lib\tkinter\__init__.py", line 1533, in __call__
      return self.func(*args)
  TypeError: login() missing 2 required positional arguments: 'username' and 'password'
  </code></pre>
  
  <p>Why do I get this error?</p>