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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 postOptions(self):
 """ Find an installed offering and set the site front page to its application's front page. """

        o = self.store.findFirst(
            offering.InstalledOffering,
            (offering.InstalledOffering.offeringName ==
             self["name"]))
        if o is None:
            raise usage.UsageError("No offering of that name"
                                   " is installed.")
        fp = self.store.findUnique(publicweb.FrontPage)
        fp.defaultApplication = o.application