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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 available(self):
 """Control availability of the viewlet """

        url = api.get_url(self.context)
        # render on the portal root
        if self.context == api.get_portal():
            return True
        # render on the front-page
        if url.endswith("/front-page"):
            return True
        # render for manage_results
        if url.endswith("/manage_results"):
            return True
        return False