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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 workspace_backup_undo(ctx):
 """ Restore the last backup """

    backup_manager = WorkspaceBackupManager(Workspace(ctx.resolver, directory=ctx.directory, mets_basename=ctx.mets_basename, automatic_backup=ctx.automatic_backup))
    backup_manager.undo()