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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 print_evaluation(period=1, show_stdv=True):
 """Create a callback that prints the evaluation results. Parameters period : int, optional (default=1) The period to print the evaluation results. show_stdv : bool, optional (default=True) Whether to show stdv (if provided). Returns ------- callback : function The callback that prints the evaluation results every ``period`` iteration(s). """

    def _callback(env):
        if period > 0 and env.evaluation_result_list and (env.iteration + 1) % period == 0:
            result = '\t'.join([_format_eval_result(x, show_stdv) for x in env.evaluation_result_list])
            print('[%d]\t%s' % (env.iteration + 1, result))
    _callback.order = 10
    return _callback