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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 cleartextRoot(self, hostname=None):
 """ Return a string representing the HTTP URL which is at the root of this site. @param hostname: An optional unicode string which, if specified, will be used as the hostname in the resulting URL, regardless of the C{hostname} attribute of this item. """

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