--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/symbian-qemu-0.9.1-12/python-2.6.1/Demo/tkinter/guido/electrons.py	Fri Jul 31 15:01:17 2009 +0100
@@ -0,0 +1,91 @@
+#! /usr/bin/env python
+
+# Simulate "electrons" migrating across the screen.
+# An optional bitmap file in can be in the background.
+#
+# Usage: electrons [n [bitmapfile]]
+#
+# n is the number of electrons to animate; default is 30.
+#
+# The bitmap file can be any X11 bitmap file (look in
+# /usr/include/X11/bitmaps for samples); it is displayed as the
+# background of the animation.  Default is no bitmap.
+
+from Tkinter import *
+import random
+
+
+# The graphical interface
+class Electrons:
+
+    # Create our objects
+    def __init__(self, n, bitmap = None):
+        self.n = n
+        self.tk = tk = Tk()
+        self.canvas = c = Canvas(tk)
+        c.pack()
+        width, height = tk.getint(c['width']), tk.getint(c['height'])
+
+        # Add background bitmap
+        if bitmap:
+            self.bitmap = c.create_bitmap(width/2, height/2,
+                                          bitmap=bitmap,
+                                          foreground='blue')
+
+        self.pieces = []
+        x1, y1, x2, y2 = 10,70,14,74
+        for i in range(n):
+            p = c.create_oval(x1, y1, x2, y2, fill='red')
+            self.pieces.append(p)
+            y1, y2 = y1 +2, y2 + 2
+        self.tk.update()
+
+    def random_move(self, n):
+        c = self.canvas
+        for p in self.pieces:
+            x = random.choice(range(-2,4))
+            y = random.choice(range(-3,4))
+            c.move(p, x, y)
+        self.tk.update()
+
+    # Run -- allow 500 movemens
+    def run(self):
+        try:
+            for i in range(500):
+                self.random_move(self.n)
+        except TclError:
+            try:
+                self.tk.destroy()
+            except TclError:
+                pass
+
+
+# Main program
+def main():
+    import sys, string
+
+    # First argument is number of electrons, default 30
+    if sys.argv[1:]:
+        n = string.atoi(sys.argv[1])
+    else:
+        n = 30
+
+    # Second argument is bitmap file, default none
+    if sys.argv[2:]:
+        bitmap = sys.argv[2]
+        # Reverse meaning of leading '@' compared to Tk
+        if bitmap[0] == '@': bitmap = bitmap[1:]
+        else: bitmap = '@' + bitmap
+    else:
+        bitmap = None
+
+    # Create the graphical objects...
+    h = Electrons(n, bitmap)
+
+    # ...and run!
+    h.run()
+
+
+# Call main when run as script
+if __name__ == '__main__':
+    main()