运行以下代码时，尽管所有文件都存在于目录中，但我收到以下文件未找到的异常：
path_to_training_dataset="CNN_assignment/Skin cancer ISIC The International Skin Imaging Collaboration/Train/" for i in class_names_list: p = Augmentor.Pipeline(source_directory=path_to_training_dataset + i) p.rotate(probability=0.7, max_left_rotation=10, max_right_rotation=10) p.sample(500) ## We are adding 500 samples per class to make sure that none of the classes are sparse. p.set_save_format("JPG") # Disable auto-cleanup p.auto_cleanup = False下面是类列表，都是文件夹名称 class_names_list=['光化性角化病'、'皮肤纤维瘤'、'黑色素瘤'、'痣'、'鳞状细胞癌'、'血管病变'、'基底细胞癌'、'色素性良性角化病'、'脂溢性角化病']