title: __init__() missing 1 required positional argument: 'widgetName'
body: <p>I want to develop a class that inherits from the tkinter menu class. Here is my code so far the implements the class <code>MyMenu</code>, creates a test instance <code>mDummy</code> afterwards and adds a command.</p>
  
  <pre><code># import tkinter
  import tkinter as tk
  # define menu class
  class MyMenu(tk.Menu):
      def __init__(self, arg_master=None, **options):
      # call superclass constructors
      super(tk.Menu,self).__init__(arg_master,**options)
  
  #define test command for menu
  def testcommand():
      print("This is a test")
  
  #start of the code    
  main=tk.Tk()
  mDummy=MyMenu(main)
  main.config(menu=mDummy)
  mDummy.add_command(label="testlabel",command=testcommand)
  
  main.mainloop()
  </code></pre>
  
  <p>the execution of the code results in a type error:</p>
  
  <pre><code>TypeError: __init__() missing 1 required positional argument: 'widgetName'.
  </code></pre>
  
  <p>Here is the full traceback:</p>
  
  <pre><code>Traceback (most recent call last):   File "C:\Program Files
  (x86)\Python34\MyProjects\tests\test_myUCVMenu.py", line 15, in &lt;module&gt;
      mDummy=MyMenu(main)   
  File "C:\Program Files (x86)\Python34\MyProjects\tests\test_myUCVMenu.py", line 7, in __init__
      super(tk.Menu,self).__init__(arg_master,**options) 
  TypeError: __init__() missing 1 required positional argument: 'widgetName'
  </code></pre>
  
  <p>From the message, I think that the <code>__init__</code> operator of the tkinter menu class wants me to give a variable <code>'widgetName'</code> as a positional argument, but I couldn't find out the meaning of <code>"widgetName"</code> in the docu. May be the error is somewhere else than in the given line but the code crashes at the call of the <code>__init__</code> operator?</p>