Tkinter example of calculation based on text fields

tkfields.py

# Trivial example adapted from a CodeSkulptor example:
# http://www.codeskulptor.org/#user39_dAIPAbXbfU_0.py

from Tkinter import Button, E, Entry, Frame, Label, StringVar, Tk, W

class Application(Frame):
    def get_initials(self):
        initials = (self.first_name.get()[:1].upper() +
                    self.last_name.get()[:1].upper())
        print "Initials:", initials

    def createWidgets(self):
        self.first_name = StringVar()
        self.last_name = StringVar()
        
        Label(self, text='First name:').grid(column=1, row=1)
        Entry(self, width=7, textvariable=self.first_name).grid(column=2,
                                                                row=1,
                                                                sticky=(W, E))
        Label(self, text='Last name:').grid(column=1, row=2)
        Entry(self, width=7, textvariable=self.last_name).grid(column=2,
                                                               row=2,
                                                               sticky=(W, E))
        Button(self,
               text="Create Initials",
               command=self.get_initials).grid(column=2, row=3)

    def __init__(self, master=None):
        Frame.__init__(self, master)
        self.pack()
        self.createWidgets()

root = Tk()
app = Application(master=root)
app.mainloop()

without_tk.py

# Same example using constants instead of a form

# Edit the constants in this section to run the calculation on your data.
FIRST_NAME = "Don"
LAST_NAME = "Kirkby"

# This is the calculation
def get_initials(first_name, last_name):
    initials = (first_name[:1].upper() + last_name[:1].upper())
    print "Initials:", initials

get_initials(FIRST_NAME, LAST_NAME)