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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 uninstall(self, xmlpath):
 """Uninstalls the repository with the specified XML path from the server. """

        from os import path
        fullpath = path.abspath(path.expanduser(xmlpath))
        if fullpath in self.installed:
            repo = RepositorySettings(self, fullpath)
            if repo.name.lower() in self.repositories:
                del self.repositories[repo.name.lower()]
            if repo.name.lower() in self.archive:
                del self.archive[repo.name.lower()]
                self._save_archive()
            self.installed.remove(fullpath)
            self._save_installed()
        else:
            warn("The repository at {} was not installed to begin with.".format(fullpath))