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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 save_form(self, request, form, change):
 """ Don't show links in the sitemap. """

        obj = form.save(commit=False)
        if not obj.id and "in_sitemap" not in form.fields:
            obj.in_sitemap = False
        return super(LinkAdmin, self).save_form(request, form, change)