Python program to find the Factorial of any number

#!/usr/bin/python
# -*- coding: utf-8 -*-
# Python program to find the factorial of a number provided by the user.
# change the value for a different result
# To take input from the user
num = int(input('Enter a number: '))
factorial = 1
# check if the number is negative, positive or zero
if num < 0:
   print 'Sorry, factorial does not exist for negative numbers'
elif num == 0:
   print 'The factorial of 0 is 1'
else:
   for i in range(1, num + 1):
       factorial = factorial * i
   print ('The factorial of', num, 'is', factorial)