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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def rootURL(self, request):
 """ Simple utility function to provide a root URL for this website which is appropriate to use in links generated in response to the given request. @type request: L{twisted.web.http.Request} @param request: The request which is being responded to. @rtype: L{URL} @return: The location at which the root of the resource hierarchy for this website is available. """

        warnings.warn(
            "Use ISiteURLGenerator.rootURL instead of WebSite.rootURL.",
            category=DeprecationWarning,
            stacklevel=2)
        if self.store.parent is not None:
            generator = ISiteURLGenerator(self.store.parent)
        else:
            generator = ISiteURLGenerator(self.store)
        return generator.rootURL(request)