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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 reset_folder(self, folder):
 """ Erase the database index from a given folder and restart Syncthing. Args: folder (str):
 Folder ID. Returns: None """

        warnings.warn('This is a destructive action that cannot be undone.')
        self.post('reset', data={}, params={'folder': folder})