#/usr/bin/python

import pygtk
pygtk.require('2.0')
import gtk

class HelloWorld:
	
	def hello(self, widget, data=None):
		print "Hello World"
	
	def delete_event(self, widget, event, data=None):
		print "delete event occurred"
		return False
	def destroy(self, widget, data=None):
		print "destroy signal occured"
		gtk.main_quit()
	
	def __init__(self):
		self.window = gtk.Window(gtk.WINDOW_TOPLEVEL)
		self.window.connect("delete_event", self.delete_event)
		self.window.connect("destroy", self.destroy)
		self.window.set_border_width(10)

		self.button = gtk.Button("Hello World")
		self.button.connect("clicked", self.hello, None)
		self.button.connect_object("clicked", gtk.Widget.destroy, self.window)
		self.window.add(self.button)
		self.button.show()
		self.window.show()
	
	
	def main(self):
		gtk.main()
		
if __name__ = "__main__":
	hello = HelloWorld()
	hello.main()

------------------------------> output

./HelloWorld.py: line 3: 16553 Segmentation fault      import pygtk
./HelloWorld.py: line 4: syntax error near unexpected token `'2.0''
./HelloWorld.py: line 4: `pygtk.require('2.0')'

------------------------------> output commenting pygtk.require('2.0')

./HelloWorld.py: line 3: 16596 Segmentation fault      import pygtk
./HelloWorld.py: line 5: 16597 Segmentation fault      import gtk
./HelloWorld.py: line 7: class: command not found
./HelloWorld.py: line 9: syntax error near unexpected token `('
./HelloWorld.py: line 9: `      def hello(self, widget, data=None):'