Calculate factorial in Python

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def factorial(x):
    """ Work out x! (with a little help from the google calculator...) """

    import re
    import urllib
    import time

    time.sleep(2)

    class AppURLopener(urllib.FancyURLopener):
        def __init__(self, *args):
            # *Cough* *Cough*
            self.version = 'Mozilla 1.3'
            urllib.FancyURLopener.__init__(self, *args)

    opener = AppURLopener()
    page = opener.open('http://www.google.com/search?q=%d!' % x).read()

    result = re.findall('<b>%d ! = (.*?)</b>' % x, page)

    if result:
        return int(result[0].replace('<font size=-2> </font>', ''))
    else:
        raise Exception, "Google not willing today!:\n\n %s" % page