from  tkinter import  *
from tkinter.colorchooser import askcolor                  

def callback():
    result = askcolor(color="#6A9662", 
                      title = "Bernd's Colour Chooser") 
    print (result)
    

root = Tk()
Button(root, 
       text='Choose Color', 
       fg="darkgreen", 
       command=callback).pack(side=LEFT, padx=10)
Button(text='Quit', 
       command=root.quit,
       fg="red").pack(side=LEFT, padx=10)
mainloop()