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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 beforeRender(self, ctx):
 """ Before rendering, retrieve the hostname from the request being responded to and generate an URL which will serve as the root for all JavaScript modules to be loaded. """

        request = IRequest(ctx)
        root = self.webSite.rootURL(request)
        self._moduleRoot = root.child('__jsmodule__')