Calling parent method inside child class python : <p>Here is my code:</p>

<pre><code>class GUI(playGame):
    def __init__(self):                          

        import tkinter as tk
        home=tk.Tk()
        home.title("Tic Tac Toe")
        home.geometry("160x180")
        w,h=6,3


        self.c1r1=tk.Button(text='',width=w, height=h, command=lambda: userTurn(self.c1r1))
        self.c1r1.grid(column=1,row=1)
        home.mainloop()
</code></pre>

<p>So, userTurn has been defined in the parent class playGame but when I run this and click on the button c1r1, I get 
NameError: name 'userTurn' is not defined</p>
