keras-retinanet 라쿤학습 시 오류

아래 구문으로 레티나넷 학습 평가를 출력할 때  

AttributeError: 'tuple' object has no attribute 'items'

오류가 나옵니다. 해결방법이 궁금합니다.

사용os은 window 10입니다.

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# print evaluation

total_instances = []

precisions = []

for label, (average_precision, num_annotations) in average_precisions.items():

    print('{:.0f} instances of class'.format(num_annotations),

          generator.label_to_name(label), 'with average precision: {:.4f}'.format(average_precision))

    total_instances.append(num_annotations)

    precisions.append(average_precision)

if sum(total_instances) == 0:

    print('No test instances found.')

print('Inference time for {:.0f} images: {:.4f}'.format(generator.size(), inference_time))

print('mAP using the weighted average of precisions among classes: {:.4f}'.format(sum([a * b for a, b in zip(total_instances, precisions)]) / sum(total_instances)))

print('mAP: {:.4f}'.format(sum(precisions) / sum(x > 0 for x in total_instances)))

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