Some refactoring.

diff --git a/qwerty.py b/qwerty.py
index 37f6aab..d864485 100755
--- a/qwerty.py
+++ b/qwerty.py
@@ -1,4 +1,5 @@
 #!/usr/bin/python
+#encoding: UTF-8

 import sys
 import os
@@ -16,6 +17,13 @@ GLOBAL = 0
 SECTION = 1
 KEY = 2

+KEYS = [ "QWERTYUIOP",
+         "ASDFGHJKL",
+         "ZXCVBNM" ]
+ALPHABET = KEYS[0] + KEYS[1] + KEYS[2]
+
+DIGITS = "0123456789"
+
 BUTTON_BORDER = (0.7,0.7,0.7)
 BUTTON_BORDER_ACTIVE = (0,0,0)
 BUTTON_FILL = (0.9, 0.9, 0.9)
@@ -267,29 +275,28 @@ class GUI(object):
     def __init__(self):
         global sections

-        A = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
         self.buttons = {}
         self.sbuttons = []
         self.by_class = {}
 #         self.by_xid = {}

-        for c in A:
+        for c in ALPHABET:
             self.buttons[c] = SuperButton(c)
             self.buttons[c].show()

-        for c in "1234567890":
+        for c in DIGITS:
             btn = SuperButton(c)
             btn.show()
             self.sbuttons.append(btn)

         self.rows = [[]]
-        for c in 'QWERTYUIOP':
+        for c in KEYS[0]:
             self.rows[0].append(self.buttons[c])
         self.rows.append([])
-        for c in 'ASDFGHJKL':
+        for c in KEYS[1]:
             self.rows[1].append(self.buttons[c])
         self.rows.append([])
-        for c in 'ZXCVBNM':
+        for c in KEYS[2]:
             self.rows[2].append(self.buttons[c])

         self.taskbar = gtk.VBox()
@@ -431,9 +438,9 @@ class GUI(object):
                 return

         k = event.string.upper()
-        if k in '1234567890':
+        if k in DIGITS:
             self.show_section(k)
-        elif k in 'ABCDEFGHIJKLMNOPQRSTUVWXYZ':
+        elif k in ALPHABET:
             self.do_button(k)
         elif k == ' ':
             self.switch_taskbar()